塌字 [－－]

Jyutping taap3 zi6
Pinyin tā zì

Definitions (Wiktionary)
  1. noun, Min-Nan
    words added in verses (to improve a literary composition)
  2. noun, Zhangzhou-Hokkien
    intagliated characters or designs
    (syn.) 陰文, 凹字, 阴文