| Barbule 1. (n.) A very minute barb or beard. 2. (n.) One of the processes along the edges of the barbs of a feather, by which adjacent barbs interlock. See Feather. Thesaurus Entries antenna, barb, barbel, barrel, cat whisker, cilium, feeler, filament, filamentule, palp, palpus, quill, shaft, tactile cell, tactile corpuscle, tactile hair, tactile organ, tactile process, tactor, vibrissa |