決定的|けっていてきketteiteki[0]heiban (flat)

1. na-adjectivedefinite; final; decisive; conclusive
   きっと無罪むざいになるだけの決定的けっていてき切り札きりふだを隠し持かくしもっているに違ちがいない。↗

   I'm sure he has something up his sleeve.

• Synonym最終的さいしゅうてきNeutralNeutral. Refers to what is final or last; 「決定的」 stresses a decisive role or an outcome already settled.
• Synonym確定的かくていてきWrittenWritten/formal prose. Means something already decided and unchangeable; 「決定的」 also covers playing a decisive role or an extreme degree.
• Related確実かくじつNeutralNeutral. Means certain and reliable, as in 「確実な方法」; 「決定的」 focuses on a settled outcome rather than dependability.
• Related明確めいかくNeutralNeutral. Means clear and unambiguous, as in 「明確な答え」; 「決定的」 stresses a settled outcome or an extreme degree.
• Related絶対的ぜったいてきWrittenWritten/formal prose. Means absolute and unconditional; 「決定的」 stresses a decisive role that leaves things all but settled.
• Antonym不確かふたしかNeutralNeutral. Opposite of 「決定的」 in certainty: it means uncertain and unreliable.
• Antonym曖昧あいまいNeutralNeutral. Opposite of 「決定的」 in clarity: it means vague and ambiguous, without a definite answer.
• Antonym暫定的ざんていてきWrittenWritten/formal prose. Opposite of 「決定的」 on finality: it means provisional, in place only for the time being.
• Antonym仮のNeutralNeutral. Means temporary or provisional, the opposite of 「決定的」's sense of an outcome already settled.

Use 「決定的」 for something that decides the outcome or is all but settled, as in 「決定的な証拠」 and 「決定的瞬間」, and for extreme degree as in 「決定的に異なる」. For something already fixed use 「確定的」; for what comes last use 「最終的」. The main antonyms are 「暫定的」 and 「曖昧」.

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

1. 物事ものごとがほぼ決きまっているさま。
2. まったくそうであるさま。程度ていどがはなはだしいさま。