noun pl. rostella -·la (-ə)

1. Bot. a sterile, flaplike modified stigma that separates the anthers from the stigmas in some orchids
2. Zool.
   1. a small, rounded projection bearing hooks on the head of certain tapeworms
   2. a beak-shaped, sucking mouthpart in certain insects

Etymology: Modl < L, dim. of rostrum: see rostrum