Polype. A species of zoophytes, whose chief animal property consists of having a stomach which is so constituted that it acts equally well if the animal is turned inside out. They propagate by stems or buds, and, when cut into parts, each part becomes a perfect animal, living in water, fixed at one end; hut myriads of them reside in small cells of corals, madrepores, etc. in forms like plants, and their multiplication and industry create rooks and whole islands in many seas.