水すい火か氷ひょう炭たん

noun

complete incompatibility; like water and oil

A literary yojijukugo describing two people or things that are fundamentally incompatible, like water and fire or ice and hot coals. Rare in everyday speech; more common in written or formal contexts.

• あの二人ふたりは水すい火か氷ひょう炭たんの間あいだ柄がらだ。

  Those two are as incompatible as fire and water.