成熟|せいじゅくseijuku[0]heiban (flat)

JLPT N1approx.Common
Definitions
  1. noun, suru verb, intransitive verbmaturity; ripeness
    進すすんで責任せきにんを取とるということは成熟せいじゅくの印しるしである。↗
    Willingness to take responsibility is a sign of maturity.
Conjugation
Dictionary form成熟する(せいじゅくする)
Polite (masu)成熟します(せいじゅくします)
Negative (nai)成熟しない(せいじゅくしない)
polite (masen)成熟しません(せいじゅくしません)
classical zu / nu成熟せず・成熟せぬ(せいじゅくせず・せいじゅくせぬ)
Past (ta)成熟した(せいじゅくした)
polite (mashita)成熟しました(せいじゅくしました)
Past negative (nakatta)成熟しなかった(せいじゅくしなかった)
polite (masen deshita)成熟しませんでした(せいじゅくしませんでした)
Te form成熟して(せいじゅくして)
Potential成熟できる(せいじゅくできる)
Passive成熟される(せいじゅくされる)
Causative成熟させる(せいじゅくさせる)
Causative passive成熟させられる(せいじゅくさせられる)
Conditional (ba)成熟すれば(せいじゅくすれば)
tara成熟したら(せいじゅくしたら)
Volitional成熟しよう(せいじゅくしよう)
polite (mashou)成熟しましょう(せいじゅくしましょう)
Imperative成熟しろ(せいじゅくしろ)

Common forms generated by rule; see the senses for honorific or irregular usage.

Synonyms & antonyms
  • Synonym熟成じゅくせいNeutralUsed for wine, meat, cheese etc. gaining flavor as they age, and for ideas or the moment slowly coming to fruition; 「成熟」 covers living things, character, or timing.
  • Synonym円熟えんじゅくNeutralPolished, seasoned mastery of an art or personality, as in 「円熟した演技」; 「成熟」 is the broader word.
  • Synonym完熟かんじゅくNeutralComplete ripeness of fruit; 「成熟」 also covers character and timing.
  • Synonym老成ろうせいNeutralBeing mature beyond one's years or seasoned with experience; 「成熟」 is more neutral in tone.
  • Synonym老熟ろうじゅくWrittenA written, rare word for seasoned maturity from long experience; in everyday speech use 「成熟」 or 「円熟」.
  • Related実るみのるNeutralA verb: to bear fruit or for efforts to pay off. 「成熟」 is about reaching a mature state, and can be used as 「成熟する」.
  • Related熟すじゅくすNeutralA verb: fruit ripening, the time being ripe, or a word becoming established through use. 「成熟」 is a noun that also takes 「する」 and covers character and mind.
  • Related熟するじゅくするWrittenA written variant of 「熟す」; 「成熟」 can also describe the maturing of character and mind.
  • Related熟れるうれるNeutralA verb for fruit or grain becoming fully ripe and ready to eat; 「成熟」 also covers character and timing.
  • Related大人びるおとなびるNeutralSaid of a child seeming grown-up; 「成熟」 is real maturity.
  • Related練れるねれるNeutralDough being well kneaded, or a person becoming seasoned and polished; 「成熟」 is the broader term.
  • Related熟むうむWrittenAn archaic, written word for ripening, rare today; say 「熟れる」 in everyday speech.
  • Antonym未熟みじゅくNeutralThe opposite of 「成熟」: unripe fruit, or an immature, inexperienced person.
  • Antonym幼いおさないNeutralThe opposite of 「成熟」 in age and mind: very young or childish.
  • Antonym稚いいとけないWrittenA literary word, opposite to 「成熟」 in age and mind: young and innocent.

Default to 「成熟」 for living things ripening, a mature character, or the right timing. Use 「熟成」 for aging wine, meat or cheese, 「円熟」 for polished skill, 「熟れる」 or 「完熟」 for fruit fully ripe, and 「大人びる」 for a child seeming grown-up. Antonyms: 「未熟」, 「幼い」.

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

Japanese definitions
  1. 果実かじつや穀物こくもつが熟じゅくすること。
  2. 適てきした時期じきになること。
  3. 十分じゅうぶんに成長せいちょうして、これ以上いじょうは成長せいちょうしない状態じょうたいに至いたること。数量すうりょうや規模きぼが、これ以上いじょうは上あがらない状態じょうたいに至いたること。
Kanji in this word
English equivalents
See also

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

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