Cestus \Ces"tus\, n. [L. cestus girdle, Gr. ?, lit., stitched, embroidered.] 1. (Antiq.) A girdle; particularly that of Aphrodite (or Venus) which gave the wearer the power of exciting love. 2. (Zo["o]l.) A genus of Ctenophora. The typical species ({Cestus Veneris}) is remarkable for its brilliant iridescent colors, and its long, girdlelike form.