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.