Here's a plain-English glossary of the most important language learning terms and terms from research on second language acquisition (SLA).

Why Know Language Learning Terms?

Learning how to learn requires some basic vocabulary.
Researchers have discovered many of our intuitions about learning a language are flat wrong, so being able to read the basics helps.
Many language obstacles require understanding the problem to solve it.

A–Z Index

A · Accent · Acquisition vs. learning · ACTFL · Active recall · Affective filter · Audiolingual method · Automatization

B · Bilingualism · Bottom-up vs. top-down processing

C · Can-do statements · CEFR · Chunking · Circumlocution · Code-switching · Cognate · Collocation · Communicative competence · Communicative language teaching (CLT) · Comprehensible input (i+1) · Comprehension threshold · Conjugation · Content-based instruction (CLIL) · Contrastive analysis · Corrective feedback · Creole · Critical period hypothesis

D · Declarative vs. procedural knowledge · DELE · Deliberate practice · Desirable difficulties · Dialect · Diglossia · Direct method · Discourse · Drill

E · Error vs. mistake · Explicit vs. implicit learning · Extensive reading

F · False friend · Flashcard · Fluency vs. accuracy · Focus on form · Focus on forms · Foreign language anxiety · Forgetting curve · Four skills · Four Strands · Frequency list · FSI categories

G · Gamification · Graded reader · Grammar-translation method · Grammatical gender

H · Heritage speaker · Honorifics · HSK

I · Ideal L2 self · IELTS · Immersion · Incidental vs. intentional learning · Input hypothesis · Input processing · Input vs. intake · Intensive reading · Interaction hypothesis · Interlanguage · Interleaving · Intermediate plateau · IPA

J · JLPT

L · L1 / L2 · Language aptitude · Language attrition · Language barrier · Language exchange · Language family · Language fossilization · Language obstacle · Language of thought (mentalese) · Language transfer · Learner autonomy · Learning styles (myth) · Lingua franca · Linguistic relativity (Sapir–Whorf) · Loanword · Logograph

M · Massed practice · Minimal pair · Mnemonics · Monitor model · Morpheme · Motivation: integrative vs. instrumental · Mutual intelligibility

N · Native speaker · Natural order hypothesis · Negotiation of meaning · Noticing hypothesis

O · Output · Overgeneralization

P · Pedagogy · Phoneme · Phrasal verb · Pidgin · Pitch accent · Polyglot (hyperpolyglot) · PPP · Pragmatics · Private speech · Processability theory · Processing instruction · Prosody (intonation) · Pushed output

R · Reading pain · Recast · Receptive vs. productive skills · Register · Retrieval practice · Romanization

S · Scaffolding · Second language acquisition (SLA) · Semantics · Sensitive period · Sentence mining · Shadowing · Silent period · Skill acquisition theory · Skimming and scanning · Slang (colloquialism) · Sociocultural theory · Spaced repetition (SRS) · Spacing effect · Storage vs. retrieval strength · Streak · Syllabary · Syntax

T · Target language · Task-based language teaching (TBLT) · Teachability hypothesis · The natural approach · TOEFL · Tone · Total physical response (TPR) · TPRS · Translanguaging · Treatable vs. untreatable errors

U · U-shaped learning · Ultimate attainment · Universal grammar

V · Vocabulary acquisition

W · Washback effect · Willingness to communicate (WTC) · Word family · Word order (SVO, SOV, VSO) · Written corrective feedback

Z · Zone of proximal development (ZPD)

Input, Reading & Listening Terms

Comprehensible input (i+1)

Language you can mostly follow, pitched just a step above your current level. The "i+1" shorthand means your level now (i) plus one small stretch. It's the engine behind most immersion advice. Full guide: comprehensible input.

Extensive reading

Reading a large volume of easy material (around 98% known words) for flow and exposure, not study. The goal is miles on the page, not decoding every word. Full guide: extensive reading.

Intensive reading

The slower opposite of extensive reading: working carefully through a harder text, dictionary in hand, to study its words and grammar closely. See also extensive reading.

Graded reader

A book written or simplified for a specific level, so a learner can read it at high comprehension instead of drowning in unknown words. See also extensive reading.

Immersion

Surrounding yourself with the language through media, travel, or daily use. Effective immersion is mostly comprehensible input at scale; simply hearing a language you can't follow does little. See also comprehensible input.

Input vs. intake

Input is everything you hear or read. Intake is the smaller slice your brain actually absorbs and can use. Closing that gap is much of the work of learning. Full guide: input vs. intake.

Input processing

The theory of why you can understand a whole sentence yet completely miss the grammar inside it, because meaning grabs your attention before form does. Full guide: input processing.

Shadowing

Playing a recording and speaking along almost immediately, copying the rhythm, sounds, and intonation like an echo a half-second behind. A popular drill for pronunciation and speaking fluency. More on the shadowing technique.

Total physical response (TPR)

Learning by acting language out physically (stand up, touch your nose) so meaning attaches to movement before you're asked to speak.

Comprehension threshold (95–98%)

The share of words you need to already know to follow something comfortably: roughly 98% for reading, 95% for listening. Below it, comprehension drops off fast. See also vocabulary acquisition.

Reading pain

The zone below about 90% known words, where so many meaning-carrying words are missing that reading turns into decoding. See also extensive reading.

Four Strands

Paul Nation's recipe for a balanced language diet: meaning-focused input, meaning-focused output, deliberate language study, and fluency practice, in roughly equal measure. See also extensive reading.

Input hypothesis

Krashen's claim that we acquire language mainly by understanding messages a little above our level, not by studying rules. It's the engine behind comprehensible input. See also comprehensible input.

Monitor model

Krashen's larger theory that consciously "learned" grammar works only as an editor (a monitor) checking output, while real fluency comes from subconscious acquisition. The monitor hypothesis is one of its five parts.

Natural order hypothesis

Krashen's observation that grammar features tend to be acquired in a roughly fixed order no matter how they're taught, which is why some rules stay hard long after a lesson covers them. See also interlanguage.

Skimming and scanning

Two fast reading modes: skimming for the overall gist, scanning to hunt down one specific detail. Both skip careful word-by-word reading.

Bottom-up vs. top-down processing

Bottom-up builds meaning from the sounds or letters upward; top-down uses context and prior knowledge to predict downward. Skilled listeners and readers blend the two.

Output, Speaking & Interaction Terms

Output

The language you produce by speaking and writing, as opposed to the language you take in. The output hypothesis argues that producing language, not just understanding it, is what pushes acquisition forward. Full guide: the output hypothesis.

Pushed output

Being nudged to say or write something just past your comfort zone, which forces you to notice the gaps in what you can actually produce. See also the output hypothesis.

Interaction hypothesis

The claim that working through misunderstandings in real conversation drives learning beyond what quiet input alone provides. Full guide: the interaction hypothesis.

Negotiation of meaning

The back-and-forth repair when a conversation stumbles: "Sorry, you mean the blue one?" Those small clarifications are where a lot of acquisition happens. See also the interaction hypothesis.

Willingness to communicate (WTC)

Your in-the-moment readiness to actually open your mouth and speak, which can lag well behind your real ability. Full guide: willingness to communicate.

Silent period

An early, input-heavy phase where a learner takes the language in before producing much of it. Useful as a bounded head start, less so as an indefinite excuse not to speak. Full guide: the silent period.

Communicative competence

Knowing not just grammar but how to use a language appropriately: reading the situation, the register, and the social cues. Grammar alone doesn't make you understood. Full guide: communicative competence.

Code-switching

Moving between two languages within a single conversation or even a single sentence, often for a word that simply lands better in the other language.

Receptive vs. productive skills

Receptive skills are the ones for taking language in (reading, listening); productive skills are the ones for putting it out (speaking, writing). Understanding almost always runs ahead of production. See also the output hypothesis.

Four skills

The traditional split of language ability into reading, listening, speaking, and writing. Reading and listening are receptive; speaking and writing are productive.

Circumlocution

Talking around a word you don't know ("the thing you open cans with") to keep the conversation moving. A core survival skill for speaking before your vocabulary catches up.

Memory, Practice & Study Terms

Spaced repetition (SRS)

Reviewing material at growing intervals, so each word comes back just as you're about to forget it. The backbone of most vocabulary apps. Full guide: spaced repetition.

Spacing effect

The well-tested finding that practice spread over time beats the same practice crammed together. It's why spaced repetition works. See also spaced repetition.

Retrieval practice

Pulling an answer out of memory (a quick self-quiz) instead of rereading it. The effort of recall is what makes it stick, an idea also called the testing effect. Full guide: retrieval practice.

Interleaving

Mixing different topics or skills within one session instead of drilling a single one in a block. It feels messier and works better. Full guide: interleaving.

Desirable difficulties

Study moves that feel harder in the moment (spacing, testing yourself, mixing things up) but build far more durable memory than easy review. Full guide: desirable difficulties.

Forgetting curve

The predictable way memory decays over time without review, steep at first and then leveling off. Spaced review is designed to interrupt it. See also language attrition.

Skill acquisition theory

How a grammar rule moves from something you consciously know to something you use automatically, through the right kind of practice. Full guide: skill acquisition theory.

Vocabulary acquisition

How a word travels from vaguely familiar to fully yours, across its form, meaning, and use, and how many words you need for real coverage. Full guide: vocabulary acquisition.

Word family

A base word plus its inflected and derived forms (help, helps, helping, helpful), counted as a single unit when measuring vocabulary size. See also vocabulary acquisition.

Collocation

Words that habitually go together. You "make a decision," you don't "do a decision," even though both are grammatical. Learning these pairings is a big part of sounding natural.

Chunking (formulaic language)

Learning multi-word phrases ("by the way," "would you mind") as single ready-made units rather than building them word by word each time.

Explicit vs. implicit learning

Explicit learning is studying rules on purpose; implicit learning is absorbing a language through exposure without conscious effort. Most learners need a mix of both. Full guide: explicit vs. implicit learning.

Declarative vs. procedural knowledge

Declarative knowledge is a rule you can state; procedural knowledge is being able to use it without thinking. Practice moves knowledge from the first kind to the second. See also skill acquisition theory.

Automatization

The process of a skill becoming fast and effortless through repeated use, so you stop assembling each sentence piece by piece. See also skill acquisition theory.

Incidental vs. intentional learning

Intentional learning is deliberately sitting down to study words or grammar; incidental learning is picking them up as a by-product of reading or listening for meaning. See also vocabulary acquisition.

Massed practice (cramming)

Piling all your study into one block. It feels productive and can pass tomorrow's test, but it fades fast next to spaced review. See also spaced repetition.

Storage vs. retrieval strength

Storage strength is how deeply something is learned; retrieval strength is how easily you can call it up right now. Effortful recall is what builds the durable kind. See also desirable difficulties.

Active recall

Studying by pulling information out of memory rather than rereading or reviewing it passively. It's the habit behind retrieval practice, and the reason a quick self-quiz beats another read-through. See also retrieval practice.

Flashcard

A two-sided prompt (word on one side, meaning on the other) for quick self-testing, most powerful when a spaced system schedules it rather than you reviewing one big pile at once. See also spaced repetition.

Sentence mining

Collecting real sentences you meet while reading or listening and turning them into review cards, so you learn words in context instead of as bare lists.

Mnemonics

Memory tricks that tie a new word to a vivid image, story, or sound, giving a slippery word a handle to grab. The keyword method and memory palace are two well-known kinds.

Deliberate practice

Focused, effortful practice aimed squarely at your weak points, with feedback, rather than comfortable repetition of what you can already do. See also skill acquisition theory.

Language exchange

Trading practice with a partner who speaks your target language and wants to learn yours, each of you taking a turn in the other's language.

Errors, Feedback & Correction Terms

Interlanguage

The learner's own evolving in-between system, part L1, part target language, with its own rules. Its errors are systematic and predictable, not random, which is a sign of progress. Full guide: interlanguage.

Language fossilization

Errors that freeze in place and stop improving even with more exposure, usually because they no longer block being understood. Full guide: language fossilization.

Language transfer

The way your first language shapes the new one, helping through similarities and interfering through differences. Full guide: language transfer.

Cognate

A word that looks or sounds alike across two languages and shares a meaning (English "family," Spanish "familia"), giving related languages a head start. See also language transfer.

False friend

A word that looks like a cognate but means something else. Spanish "embarazada" means pregnant, not embarrassed. See also language transfer.

Focus on form

Brief, in-passing attention to a grammar point during otherwise meaning-focused communication, as opposed to isolated grammar drills. Full guide: focus on form.

Recast

When a partner repeats your sentence back in corrected form without stopping to explain ("Ah, you went to the store"), a gentle correction learners often don't even notice. See also focus on form.

Noticing hypothesis

The claim that language only becomes usable once you consciously notice it in the input; what goes unnoticed tends not to stick. Full guide: the noticing hypothesis.

Written corrective feedback

Marking the errors in a learner's writing, and the long-running debate over which kinds of correction actually help. Full guide: written corrective feedback.

Minimal pair

Two words that differ by a single sound, like ship and sheep, used to train the ear on contrasts your first language may not distinguish.

Morpheme

The smallest unit of language that carries meaning: the "-s" that makes cats plural, the "un-" that flips undo.

U-shaped learning

When a learner gets a form right, then temporarily "wrong" (goed instead of went) while over-applying a new rule, before landing back on correct. It looks like backsliding but signals progress. See also interlanguage.

Teachability hypothesis

The idea that a grammar point sticks only when the learner is developmentally ready for it, no matter how early it's introduced. See also interlanguage.

Processability theory

The claim that grammar is acquired in a fixed sequence of stages that can't be skipped, because each stage depends on the mental processing the previous one built. See also interlanguage.

Treatable vs. untreatable errors

Treatable errors follow a rule you can look up (subject-verb agreement); untreatable ones (word choice, some prepositions) don't, so correction helps the first far more than the second. See also written corrective feedback.

Contrastive analysis

The older idea that lining up two languages side by side predicts a learner's errors from wherever the languages differ. Partly right, but many predicted errors never show up. See also language transfer.

Corrective feedback

Any signal that something you said or wrote was off, from a raised eyebrow to an explicit fix. It's the umbrella term over recasts, prompts, and written corrections. See also focus on form.

Error vs. mistake

An error comes from not yet knowing a rule; a mistake is a momentary lapse on something you already know and could correct yourself. One needs teaching, the other just needs attention.

Overgeneralization

Stretching a rule too far, like saying "goed" or "childs" after learning the regular pattern. Usually a sign the rule has been learned, not a bad habit forming. See also interlanguage.

Motivation, Mindset & the Learner Terms

Affective filter

The idea that stress, low confidence, and anxiety act like a valve that blocks input from getting in, even when the material is right. Full guide: the affective filter.

Ideal L2 self

The vivid mental image of a future you who already speaks the language, which turns out to be one of the strongest motivators for sticking with it. Full guide: the ideal L2 self.

Sociocultural theory

A view of learning as something built socially, through interaction and support from more capable others, rather than purely inside one head. Full guide: sociocultural theory.

Zone of proximal development (ZPD)

The sweet spot of tasks you can't quite do alone yet but can manage with a little help, where the most learning happens. See also sociocultural theory.

Scaffolding

Temporary support (a hint, a glossary, a patient conversation partner) that carries you through a task and is gradually removed as you can stand on your own. See also sociocultural theory.

Foreign language anxiety

The specific nervousness some learners feel using a new language, speaking most of all, which can block both input and performance even when the underlying ability is fine. See also the affective filter.

Private speech

Talking to yourself in the target language, out loud or in your head, which research treats as genuine practice rather than a quirk. See also sociocultural theory.

Motivation: integrative vs. instrumental

Integrative motivation is wanting to connect with a language's people and culture; instrumental is wanting a concrete payoff like a job or a passing grade. Both work, and most learners feel some of each. See also the ideal L2 self.

Language aptitude

A knack for picking up languages, often measured through sound memory and pattern-spotting. It affects how fast you learn more than how far you can go, and it isn't fixed for life. See also are polyglots different?.

Learning styles (myth)

The popular belief that each person learns best in a fixed "style" (visual, auditory, kinesthetic). Widely taught, but studies that match teaching to a learner's supposed style find no real benefit.

Streak

A running count of consecutive days practiced, used to build a habit. Good for showing up consistently, though a long streak can end up rewarding attendance more than real improvement.

Gamification

Adding game-like elements (points, levels, badges, streaks) to study to keep learners engaged. Helpful for building the habit, less so for the deeper work of actually using the language.

Teaching Methods & Pedagogy Terms

Pedagogy

The overall method and theory of teaching. In language learning it covers how a course sequences material, what it asks learners to do, and the reasoning behind those choices.

Grammar-translation method

The old-school approach built on memorizing rules and translating sentences back and forth. Strong for reading and exams, weak for actually speaking.

Audiolingual method

A mid-century method based on repetition and pattern drills, on the theory that a language is a set of habits to be trained in. It produces fluent parroting but fragile real conversation.

Direct method

Teaching entirely in the target language with no translation, where meaning is carried by demonstration, pictures, and context.

Communicative language teaching (CLT)

The mainstream modern approach that treats real communication, not flawless grammar, as the goal, building lessons around meaningful tasks. See also communicative competence.

Task-based language teaching (TBLT)

A branch of communicative teaching where learners complete real-world tasks (plan a trip, solve a problem) and pick up the language in the process.

The natural approach

A method built on plenty of comprehensible input and a low-anxiety classroom, where speaking is allowed to emerge on its own rather than being forced early. See also comprehensible input.

TPRS (teaching proficiency through reading and storytelling)

A classroom method that drives heavy repetition through highly comprehensible, interactive stories. Full guide: TPRS.

PPP (presentation, practice, production)

A common lesson shape: introduce a form, drill it in controlled practice, then use it more freely.

Focus on forms

Teaching grammar as a pre-planned syllabus of isolated rules, one at a time. The plural "forms" marks the contrast with focus on form, which handles grammar in passing during communication. See also focus on form.

Content-based instruction (CLIL)

Learning a subject such as history or science through the target language, so the language becomes the medium rather than the topic. CLIL stands for content and language integrated learning.

Drill

A short, repetitive exercise that rehearses one pattern until it's automatic. Useful in small doses, hollow as a whole method.

Processing instruction

A teaching method that changes how learners parse a sentence so they stop skipping over the grammar, rather than drilling them on production. See also input processing.

Translanguaging

Letting learners draw on their whole language range, first language included, as one connected system rather than forcing the languages to stay strictly apart.

Learner autonomy

A learner's ability to take charge of their own study: setting goals, choosing materials, and judging their own progress without a teacher steering every step.

Stages, Levels & Assessment Terms

Second language acquisition (SLA)

The research field that studies how people learn languages beyond their first, and the source of most terms in this glossary. Full guide: second language acquisition.

Acquisition vs. learning

Krashen's distinction between "acquiring" a language subconsciously through exposure and "learning" it consciously through study, along with his contested claim that only acquisition builds real fluency. See also second language acquisition.

CEFR

Common European Framework of Reference for Languages: the A1-to-C2 scale that describes what you can actually do at each level, from ordering a coffee to arguing a point. A1 is beginner; C2 is native-like. See also realistic CEFR timelines.

Intermediate plateau

The stall many learners hit around B1, where progress stops feeling visible. Less a single wall than a cluster of separate, fixable obstacles. Full guide: the intermediate plateau.

Critical period hypothesis

The much-debated idea that there's an age window for reaching native-like ability, often overstated into "you're too old to learn." Full guide: the critical period hypothesis.

Language attrition

Losing a language you once knew through disuse, with vocabulary usually fading before grammar. Often recoverable faster than it was first learned. Full guide: language attrition.

Language barrier

Communication trouble between two people who don't share a language, resolved with translation or a shared bridge language. Distinct from the internal obstacles a single learner faces. Full guide: language barrier vs. obstacle.

Language obstacle

A pedagogical term for a stage-specific sticking point inside one learner's process, the recurring point in the timeline to fluency where motivated learners get stuck and quit. Unlike a language barrier, which sits between two people, an obstacle sits inside the learner, and each one calls for a different fix rather than simply more effort. Full guide: language obstacles.

Washback effect

The way a looming exam reshapes what learners actually study, sometimes usefully, often by over-weighting whatever the test happens to score. See also the language tests guide.

ACTFL

The American proficiency scale (Novice through Distinguished), the US counterpart to the CEFR, common in schools and government. See also the language tests guide.

FSI categories

The US Foreign Service Institute's grouping of languages by how long they take English speakers to reach working proficiency, from Category I (Spanish, French) to the far longer Category IV (Mandarin, Arabic, Japanese, Korean). See also realistic CEFR timelines.

Sensitive period

A gentler version of the critical period: not a hard cutoff at a certain age, but a stretch of years when language learning tends to come more easily. See also the critical period hypothesis.

Ultimate attainment

How far a learner ends up getting in a second language, the ceiling they eventually reach, often invoked in debates over whether adults can sound native. See also the critical period hypothesis.

Heritage speaker

Someone raised around a home language they understand but may not have fully developed, sitting somewhere between native speaker and learner. See also language attrition.

Polyglot (hyperpolyglot)

Someone who speaks many languages; "hyperpolyglot" usually means roughly six or more. The advantage turns out to be mostly method and mileage, not special wiring. See also are polyglots different?.

Can-do statements

Plain descriptions of what a learner can actually do at a level ("I can order a meal and ask simple questions"), the backbone of how the CEFR defines each rung. See also realistic CEFR timelines.

JLPT

The Japanese-Language Proficiency Test, graded from N5 (easiest) to N1 (hardest), with no speaking section. See also the language tests guide.

HSK

The main standardized test of Mandarin Chinese for non-native speakers, running from the beginner bands up through advanced. See also the language tests guide.

TOEFL

A widely accepted English test for university admission, scored across the four skills and common for study in the US. See also the language tests guide.

IELTS

Another major English proficiency test, used for study, work, and migration, reported on a 9-band scale. See also the language tests guide.

DELE

The official Spanish proficiency certificate from Spain's Instituto Cervantes, mapped to the CEFR levels. See also the language tests guide.

Foundational & Linguistics Terms

L1 / L2

L1 is your first, native language; L2 is any language learned afterward. The shorthand shows up constantly in research as a fast way to say which language is which.

Target language

The specific language you're currently learning, your active L2.

Lingua franca

A shared bridge language used between people whose first languages differ, the role English most often plays today.

Register

The level of formality you shift between depending on the situation: the way you text a friend versus how you'd email a stranger.

Pragmatics

How meaning depends on context and social cues, not just literal words. It's the difference between "Can you pass the salt?" as a real question and as a request.

Accent

The pattern of pronunciation that marks where a speaker is from, or that a language isn't their first. Separate from grammar or word choice: you can be fully fluent and still keep an accent.

Dialect

A regional or social variety of a language with its own vocabulary, grammar, and pronunciation, still broadly understandable to speakers of other dialects of the same language.

Diglossia

When a community keeps two varieties of a language for different settings: a formal one for writing and official life, an everyday one for home and the street, as with Arabic.

Idiom

A fixed expression whose meaning isn't the sum of its words. "It's raining cats and dogs" has nothing to do with animals.

Slang (colloquialism)

Informal, often short-lived vocabulary tied to a group or a moment. It signals belonging and rarely shows up in textbooks.

Prosody (intonation)

The music of speech: the rhythm, stress, and rise and fall of pitch that carry meaning and feeling beyond the words themselves.

Fluency vs. accuracy

Fluency is speaking smoothly and at a natural pace; accuracy is getting the grammar and words right. They often pull against each other, and good practice balances the two.

Phoneme

The smallest unit of sound that changes meaning in a language. The difference between "pat" and "bat" is a single phoneme.

Syntax

The rules for how words combine into phrases and sentences: word order and structure.

Semantics

The study of meaning in language, at the level of individual words and whole sentences.

Discourse

Language above the level of the single sentence: how sentences link into a coherent conversation, paragraph, or story.

Language of thought (mentalese)

The hypothesis that we think in a pre-verbal mental code, with each language we speak sitting on top as an output channel rather than as the thoughts themselves. See also language of thought.

Linguistic relativity (Sapir–Whorf)

The competing idea that the language you speak shapes how you think, well supported for things like color and time, weaker for core logic and spatial reasoning. See also language of thought.

Phrasal verb

A verb plus a small word (up, off, into) whose combined meaning you can't guess from the parts: "give up," "run into," "look after." A notorious hurdle in English.

Loanword

A word borrowed from another language and used more or less as-is, like "sushi," "kindergarten," or "café."

Frequency list

A ranked list of a language's most-used words, the basis for "learn the top 1,000 words first" advice, since a few thousand words cover most of everyday speech. See also vocabulary acquisition.

IPA (International Phonetic Alphabet)

A standard set of symbols where each sign maps to exactly one sound, so you can read a word's pronunciation no matter how it's spelled.

Tone

In tonal languages like Mandarin or Vietnamese, the pitch pattern on a syllable changes the word's meaning, so one set of sounds can be several different words.

Pitch accent

A lighter relative of tone, as in Japanese, where which syllable carries a drop in pitch can tell otherwise identical words apart.

Universal grammar

Chomsky's theory that humans are born with a built-in blueprint for language, which would explain why children pick up grammar so fast from limited input. Influential and still debated.

Conjugation

Changing a verb's form to match tense, person, and number: I go, she goes, we went. Some languages pack dozens of forms into a single verb.

Grammatical gender

A system that sorts nouns into classes (masculine, feminine, sometimes neuter) that ripple out to the words around them, as in Spanish "la mesa" versus "el libro."

Word order (SVO, SOV, VSO)

The default sequence of subject, verb, and object in a language. English is subject-verb-object; Japanese is subject-object-verb; Arabic often puts the verb first.

Honorifics

Grammar and vocabulary that encode respect and social rank, built deep into languages like Japanese and Korean, where the wrong politeness level stands out immediately.

Syllabary

A writing system where each symbol stands for a whole syllable rather than a single sound, like Japanese hiragana and katakana.

Logograph (logogram)

A written symbol that stands for a whole word or idea rather than a sound, as with Chinese characters.

Romanization

Writing a non-Latin-script language in the Roman alphabet, like pinyin for Mandarin or romaji for Japanese, as a bridge for beginners who can't yet read the native script.

Native speaker

Someone who grew up speaking a language from early childhood. A common yardstick for proficiency, though a fuzzier one than it first sounds.

Bilingualism

Using two languages regularly. It comes in flavors: simultaneous (both from birth), sequential (one and then another), and balanced (roughly equal command of each).

Language family

A group of languages descended from one common ancestor, like the Romance family (Spanish, French, Italian) from Latin. Close relatives tend to be easier to learn in bulk.

Mutual intelligibility

How much speakers of two different languages or dialects can understand each other with no study, as with Spanish and Portuguese or Norwegian and Swedish.

Pidgin

A stripped-down language that springs up so groups with no shared tongue can trade or work together, with simple grammar and a small vocabulary.

Creole

What a pidgin becomes once a new generation grows up speaking it as a full native language, with rich grammar of its own. See also languages of the future.

The Tool That Turns These Language Learning Terms Into Practice

Knowing the vocabulary is the easy half. The hard half is a single study routine that actually applies it:

Reading and listening pitched at your level, so input is comprehensible instead of noise.
Speaking practice that lets you shadow and produce output, not just recognize.
Review that spaces itself, so words come back before the forgetting curve wins.
Feedback that catches the errors likely to fossilize, in plain language.

Atlas Runa is a language-learning app that takes language learning concepts and turns them into reality. Its reading library serves level-graded stories as comprehensible input, and every word you tap is saved and returned on a spaced schedule with no deck to maintain. Speaking practice covers shadowing and talk-back conversation, interactive AI writing gives rule-tagged corrections on your own sentences from Runa, the AI coach the words you've been working on.

The terms in this glossary describe how languages are learned; Atlas Runa ties together the best practice sessions, informed by decades of research in what works best.