極まる / 極まりない【きわまる / きわまりない】

極まる and 極まりない both mean "extremely", "utterly": the quality has gone as far as it can go. They follow a な-adjective directly, with no な or だ in between, and come either at the end of the sentence or before a noun. 極まりない looks negative but means the same as 極まる – literally "has no limit".

• × 失礼な極まりない → 失礼極まりない

The adjective is nearly always a critical one written in kanji: しつれい失礼, ぶれい無礼, きけん危険, めいわく迷惑, ふゆかい不愉快, むせきにん無責任. A few positive ones such as つうかい痛快 and ぜいたく贅沢 also occur.

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Both forms are formal and written: editorials, complaints, speeches. Of the two, 極まりない is the one you meet more. In conversation, すごく or ほんとうに本当に before the adjective says the same thing: ほんとうに本当にしつれい失礼だ.

Usage notes

These go beyond the adjective + 極まる pattern.

極めて

きわめて極めて is the adverb from the same verb. It goes before the adjective and keeps its な or だ: きわめて極めてきけん危険だ. It is formal, but less sharp than 極まりない.

感極まる

かんきわまって感極まって is a set phrase: "overcome with emotion", usually to the point of tears or losing your words.