无底洞

Traditional (Taiwan): 無底洞

wúdǐdòng ㄨˊ ㄉㄧˇ ㄉㄨㄥˋ

    • bottomless pit

Character by character

Saying俗语俗語

Idiom惯用语 · In everyday use

Literally
bottomless pit
Meaning
Something that swallows endless money or demands, or a desire that can never be satisfied. Usually critical or resigned.

Sources