鐵交椅

Simplified: 铁交椅

tiějiāoyǐ ㄊㄧㄝˇ ㄐㄧㄠ ㄧˇ

    • perfectly secure leadership post held for a long time

Character by character

Saying俗语俗語

Idiom惯用语 · Rarely used now

Literally
iron chair of command
Meaning
A leadership post that is perfectly secure and held for a long time with no risk of removal. Often slightly critical.

Sources