齧牙 [啮－]

Jyutping jit6 ngaa4
Pinyin niè yá

Definitions (Wiktionary)
  1. verb, Cantonese
    to grind one's teeth (during sleep)
    (syn.) 哺齿, 磨牙, 咬喙齿, 咬喙齒根, 哺齒, 咬喙齿根, 咬喙齒

齧牙 [啮－]

Jyutping ngit6 ngaa4
Pinyin niè yá

Definitions (CC-CANTO)
  1. to grind one's teeth; to gnaw one's teeth