a. [ Zoo- + -oid. ] (Biol.) Pertaining to, or resembling, an animal. [ 1913 Webster ]

n. 1. (Biol.) An organic body or cell having locomotion, as a spermatic cell or spermatozooid. [ 1913 Webster ]

2. (Zool.) (a) An animal in one of its inferior stages of development, as one of the intermediate forms in alternate generation. (b) One of the individual animals in a composite group, as of Anthozoa, Hydroidea, and Bryozoa; -- sometimes restricted to those individuals in which the mouth and digestive organs are not developed. [ 1913 Webster ]

a. Of or pertaining to a zooid; as, a zooidal form. [ 1913 Webster ]