TEN'TACLE, n. [L. tentacula.] A filiform process or organ, simple or branched, on the bodies of various animals of the Linnean class Vermes, and of Cuvier's Mollusca, Annelides, Echinodermata, Actinia, Medusae, Polypi, &c. either an organ of feeling, prehension or motion, sometimes round the mouth, sometimes on other parts of the body.