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Pronunciation: taks-on'o-me

Definition: The systematic classification of living things or organisms. Kingdoms of living organisms are divided into groups (taxa) to show degrees of similarity or presumed evolutionary relationships, with the higher categories being larger, more inclusive, and more broadly defined, and the lower categories being more restricted, with fewer species more closely related. The divisions below kingdom are, in descending order: phylum, class, order, family, genus, species, and subspecies (variety). Infra- and supra- or sub- and super- categories can be used when needed; additional categories, such as tribe, section, level, group, etc., are also used.

[G. taxis, orderly arrangement, + nomos, law]

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.