(n.) A movable, articulated organ of sensation, attached to the heads of insects and Crustacea. There are two in the former, and usually four in the latter. They are used as organs of touch, and in some species of Crustacea the cavity of the ear is situated near the basal joint. In insects, they are popularly called horns, and also feelers. The term in also applied to similar organs on the heads of other arthropods and of annelids.

aerials barb barbel barbule bedspring type cat whisker directional antenna dish doublet feed-and-reflector unit feeler mast mattress type palp palpus reflector rhombic antenna scanner strike radar scanner tactile cell tactile corpuscle tactile hair tactile organ tactile process tactor tower transmitting antenna vibrissa wave antenna