Translation guide
Expresses that something is absurd, ridiculous, or contrary to reason. Japanese often uses phrases like とんでもない, ばかげている, or ありえない to convey this.
To describe a statement, idea, or situation as completely unreasonable or laughably illogical.
A versatile expression meaning 'outrageous', 'absurd', or 'unthinkable'. Can be used to reject an accusation or describe a preposterous idea.
To emphasize that something goes against basic logic or what is generally accepted as reasonable.
Literally 'unthinkable by common sense'. A natural way to say something is preposterous from a rational standpoint.
彼の行動は常識では考えられない。
His behavior is preposterous.
とんでもない can express strong denial or modesty (e.g., when receiving a compliment), while ばかげている is a direct judgment of foolishness. For calling an idea preposterous, both work, but とんでもない is slightly more versatile.
「素晴らしいですね」「とんでもないです」
"That's wonderful." "Not at all (you're too kind)."
Direct translations like '不合理な' (fugōri na) are not commonly used to express 'preposterous' in natural conversation. Stick to the idiomatic phrases above.
そんな話はとんでもない。
That story is preposterous.
とんでもない間違いだ。
It's a preposterous mistake.
Literally 'it is foolish/stupid'. Commonly used to call something absurd or ridiculous.
その提案はばかげている。
That proposal is preposterous.
Means 'impossible' or 'unthinkable'. Often used in casual speech to express that something is beyond belief.
そんなことありえないよ。
That's preposterous!
A formal, literary term meaning 'absurd' or 'nonsensical'. Used in writing or serious commentary.
彼の理論は荒唐無稽だ。
His theory is preposterous.
Means 'doesn't make sense' or 'illogical'. Suitable for calling out flawed reasoning.
その説明は理屈に合わない。
That explanation is preposterous.