炸牛屎 [－－－]

Jyutping zaa3 ngau4 si2
Pinyin zhà niú shǐ

Definitions (粵典–words.hk)
  1. 動詞
    將​炮仗​放​喺​牛​屎​點​火​炸​開​，​係​以前​農村細​路​嘅​玩意
    to set off firecrackers in cow dung, historically common in play among village children