老鼠屎 [－－－]

Jyutping lou5 syu2 si2
Pinyin lǎo shǔ shǐ

Definitions (粵典–words.hk)
  1. 名詞
    一個​團隊​入面​最差​、​會​搞​破​壞​嘅​人
    bad apple in a group
Definitions (Wiktionary)
  1. noun, figuratively
    bad apple