Noun, pl. antennae or antennas
1. In biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes. (wikipedia.org)
2. Either of a pair of long, thin sensory appendages on the heads of insects, crustaceans, and some other arthropods. (Google Dictionary)
3. One of the jointed, movable, sensory appendages occurring in pairs on the heads of insects and most other arthropods. (dictionary.com)
Word origin: From Latin antenna, nautical term for yard and common term for pole, of unknown origin.