自廢武功 [－废－－]

Jyutping zi6 fai3 mou5 gung1
Pinyin zì fèi wǔ gōng

Definitions (粵典–words.hk)
  1. 語句
    做​咗​啲​嘢​，​令到​原本​擅長​、​叻​嘅​事​變​得​渣
    self-defeating