〜だに
Formation
Meaning
Indicates that even a small action or thought is enough to cause a strong reaction, or emphasizes that something did not happen at all (especially with negative verbs).
Note
A formal and literary expression that survives primarily in fixed phrases. It expresses that 'simply' doing A is enough to trigger B (e.g., 'imagining' is enough to feel 'fear'). Common collocations include '想像するだに' (just imagining), '考えるだに' (just thinking), and '夢にだに' (even in a dream).
Examples
そんなことが起ころうとは、想像するだに恐ろしい。
The thought of such a thing happening is terrifying even just to imagine.
あの巨大な地震の被害は、考えるだに胸が痛む。
Just thinking about the damage from that massive earthquake makes my heart ache.
彼が犯人だなんて、夢にだに思わなかった。
I never even dreamed that he could be the culprit.
宝くじで一億円当たるなんて、夢にだに見たことがない。
I've never even dreamed of winning 100 million yen in the lottery.
微動だにせず、彼は獲物を待ち続けた。
He continued to wait for his prey, without moving even a muscle.
消息だに聞かない彼だが、どこで何をしているのだろうか。
I haven't heard even a whisper of news about him; I wonder where he is and what he's doing.