lappet
From ZooTerms (Dictionary of Invertebrate Zoology)
lappet (noun; Anglo-Saxon laeppa, a loose hanging part): 1. A fold, small flap, lobe or loose hanging portion.
2. (Arthropoda: Crustacea) In Mysidacea, a ventrally projecting subdivision of the pleura.
3. (Cnidaria: Scyphozoa) A flaplike projection on the bell margin.
4. (Echinodermata: Crinoidea) A movable plate on the margin of an ambulacral groove.
5. (Echiura) In Bonellidae, the shortened arms of the proboscis.
6. (Platyhelminthes: Turbellaria) In Tricladida, earlike process on the head.
