酸 — acid / sour

Grade 5さん, す

Radical ⾣ · radical 164 The building block this kanji is filed under

酸 (readings: さん, す; Japanese kanji) means “acid / sour”. It is a Grade 5 Kyōiku kanji, taught in year 5 of Japanese elementary school, and appears in words such as 酸素 (oxygen).

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What does 酸 mean?

Full details, readings & example

Kanji	酸
Meaning	acid / sour
Readings	さん, す
Grade	Grade 5 (Hard)
Curriculum	Kyōiku kanji · Japanese elementary school
Example	酸素 (oxygen)

How to read 酸

酸 is read さん or す depending on the word.

Words with 酸

酸素oxy
硝酸axit nitric

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Updated: 2026-08-09