1. One who, or that which, feels.
2. (Science: entomology, zoology) One of the sense organs or certain animals (as insects), which are used in testing objects by touch and in searching for food; an antenna; a palp. Insects . . . Perpetually feeling and searching before them with their feelers or antennae. (Derham)
3. Anything, as a proposal, observation, etc, put forth or thrown out in order to ascertain the views of others; something tentative.
Sensitivity similar to that of a receptor organ; he had a special antenna for public relations.One of a pair of mobile appendages on the head of e.g. Insects and crustaceans; typically sensitive to touch and taste.