not be caught dead

Verb

idiomatic

(idiomatic) To refuse completely to do something, generally out of scorn.

Japanese Meaning

決して〜しない、絶対に〜するなんてありえないという強い拒否の意思を表す / （しばしば侮蔑的／あきれる様子で）断固として〜を拒む

I would not be caught dead wearing that neon jacket to a formal wedding.

あんな蛍光色のジャケットをフォーマルな結婚式で死んでも着ない。

Sense（1）

(idiomatic) To refuse completely to do something, generally out of scorn.

I would not be caught dead in such a skimpy dress.