硬骨头

Traditional (Taiwan): 硬骨頭

yìnggǔtou ㄧㄥˋ ㄍㄨˇ ˙ㄊㄡ

    • resolute individual
    • a hard nut to crack
    • tough mission
    • difficult task

Character by character

Saying俗语俗語

Idiom惯用语 · In everyday use

Literally
hard bone
Meaning
A tough, unyielding person who isn't afraid of hardship; also a hard task. Approving.

Sources