腰桿粗

Simplified: 腰杆粗

yāogāncū ㄧㄠ ㄍㄢ ㄘㄨ

    • to be strong with solid backing
    • to act with confidence

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
thick in the waist
Meaning
Strong and powerful, with solid backing; one can speak or act with confidence. Often seen as 腰杆子硬.

Sources