zo·oid (z??oid?)n. One of the distinct individuals of a colonial invertebrate animal, such as a bryozoan, that arise asexually by budding.zo·oid?al (-oid?l) adj.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.zooid (?z????d) n1. (Zoology) any independent animal body, such as an individual of a coelenterate colony2. (Biology) a motile cell or body, such as a gamete, produced by an organism zo?oidal adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014zo?oid (?zo? ??d) n. 1. any of the distinct individuals of an animallike compound or colonial organism, as a polyp of a bryozoan. adj. 2. Also, zo?oi?dal. pertaining to, resembling, or of the nature of an animal. [1850?55;