烏批 [乌－]

Jyutping wu1 pai1
Pinyin wū pī

Definitions (Wiktionary)
  1. noun, Hokkien, Quanzhou, Xiamen
    anonymous letter
  2. noun, Zhangzhou-Hokkien
    blackmail letter (by bandits or outlaws)
    (syn.) 乌单, 烏單