zooidPronunciation: /ˈzuːɔɪd, ˈzəʊ-, ˈzuːɪd/Definition of zooid noun Zoology an animal arising from another by budding or division, especially each of the individuals which make up a colonial organism and typically have different forms and functions. Derivatives zooidalPronunciation: /zuːˈɔɪd(ə)l, zəʊ-, ˈzuːɪd(ə)l/ adjective Origin: mid 19th century: from zoo- 'relating to animals' + -oidzooid in other Oxford dictionaries Definition of zooid in the US English dictionary