seta

seta (noun; plural setae; Latin seta, bristle): 1. A bristle, hair or filament process of the cuticle with which it articulates or through which it protrudes

See also: poison seta, penial seta. 2. (Annelida) Chaeta. 3. (Arthropoda: Insecta) Hollow structures formed as extensions of the epidermal layer; macrotrichia or scales. 4. (Arthropoda: Crustacea) In Cirripedia, a bristle or spine on trophi and cirri.