屁股蛋子 [－－－－]

Jyutping pei3 gu2 daan2 zi2
Pinyin pì gu dàn zi

Definitions (Wiktionary)
  1. noun, Mandarin, dialectal
    buttock; butt cheek
    (syn.) 屁股爿, 尻川䫌, 尻川𱂮, 屁股臀子