expression, noun
quick bath; hurried bath
Idiomatic expression likening a very short bath to a crow's quick dip in water. Often used humorously or critically.
彼はいつもカラスの行水で、すぐに出てくる。
He always takes a quick bath and comes out right away.
カラスの行水じゃ
It's not a crow's bath, so why don't you take a longer soak?