frenulum
From ZooTerms (Dictionary of Invertebrate Zoology)
frenulum (noun; plural frenula; Latin diminutive frenum, bridle): 1. (Arthropoda: Insecta) The strong spine or group of bristles on the humeral angle of the hind wing, that projects beneath the fore wing, uniting them in flight; frenum.
2. (Cnidaria) Gelatinous fold supporting the subumbrella of certain jellyfish.
3. (Pogonophora) A v-shaped cuticular thickening held in an epidermal groove that functions as an adhesive device; also called bridle.
