How to say "vocabulary" in Japanese

Choosing the right word

単語たんごJLPT N3approx.Common
nounReally 'word' — a single word. Its 'vocabulary' sense is words as items to learn or memorize, as when studying vocabulary; for vocabulary as someone's overall stock of words, it is not what you want.
これらの単語たんごを一ひとつずつ覚おぼえなさい。↗
Learn these words, one by one.
語彙ごいJLPT N1approx.Common
nounVocabulary as a collective body of words: a person's vocabulary, a language's vocabulary, or a field's specialized terminology. Use it when talking about how rich or broad someone's vocabulary is.
読書どくしょは語彙ごいを増ふやすのに役やくに立たつ。↗
Reading helps you build up your vocabulary.

Use 単語 when thinking of vocabulary as individual words to learn or memorize, and 語彙 for vocabulary as a whole body of words — a person's or language's stock of words, or a field's terminology.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese equivalents

単語たんごword
語彙ごいvocabulary
ボキャブラリーvocabulary
レキシコンlexicon (of a person, branch of knowledge, etc.)
単語篇たんごへんglossary
用語集ようごしゅうglossary

JLPT vocabulary levels are community estimates, not official (no official lists have been published since the 2010 revision).

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