蟬翼 [蝉－]

Jyutping sim4 jik6
Pinyin chán yì

Definitions (CC-CEDICT)
  1. cicada's wing
  2. fig. diaphanous
  3. delicate texture
Definitions (Wiktionary)
  1. noun, literary
    cicada's wing
  2. noun, figuratively, literary
    something thin/fragile/delicate