成人
せいじん
seijin
JLPT N3nounVocabularyLevel 29 - JLPT N3
Quick answer
成人 (せいじん (seijin)) means "Adult". It is read せいじん (seijin). This page covers its usage with example sentences.
Meaning
Adult
Also : Grown-up · Mature person
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Example Sentences
18歳で成人になる。
じゅうはっさいでせいじんになる。
One becomes an adult at 18 years old.
彼は成人になって、初めて一人で生活することにした。
かれはせいじんになって、はじめてひとりでせいかつすることにした。
He became an adult and decided to live alone for the first time.
Kanji in this word
Grammar to study at this level
- [Verb dictionary/nai form] + ように～ように (you ni) - So that
- [Verb dictionary form] + ことにする～ことにする (koto ni suru) - Decide to
- [Verb dictionary form] + ことになる～ことになる (koto ni naru) - It has been decided that
- [Noun/Verb te-form] + ばかり～ばかり (bakari) - Only / Nothing but
- [Verb/Adjective plain form] + はずだ～はずだ (hazu da) - Should be / It is expected
Last updated Jun 18, 2026
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