Definitions

yǎn operculum (Latin: little lid); a covering flap (in various branches of anatomy)

Etymology phono-semantic

armor

Semantic: Phonetic:

About

The character (simplified from ) is a phono-semantic compound whose traditional form paired the phonetic with the semantic radical , meaning shell or armor; the simplified version preserves this structure using and . It refers to two protective anatomical features in crustaceans and mollusks: the thin abdominal flap beneath a crab, commonly called the crab's navel, and the operculum, the hard, lid-like plate that marine snails use to seal their shells. The term appears almost exclusively in marine biology, zoological descriptions, and seafood-related contexts.