zooid /ˈzəʊɔɪd/noun 3adjective 1forms 4 noun3 •One of the individual animals in a composite group, as of Anthozoa, Hydrozoa, and Bryozoa; — sometimes restricted to those individuals in which the mouth and digestive organs are not developed. •An animal in one of its inferior or early stages of development, as one of the intermediate forms in alternate generation. •An organic body or cell having locomotion, as a spermatic cell or spermatozoid. adjective1 •Relating to, or resembling, an animal. formszooids · zoöids · more zooid · most zooid