1with object To give a zoological character to; to present or treat as animal-like; to consider in zoological terms.
2no object To engage in the study of zoology; especially to look for animals in their natural habitats for the purpose of recording or studying them zoologically. Also occasionally with object: to record or study (an animal or animals) zoologically; to record or study the fauna of (an area).
Mid 19th century; earliest use found in The Spectator. From zoology + -ize.