n. pl. cat·e·go·ries
1. A specifically defined division in a system of classification; a class.
2. A general class of ideas, terms, or things that mark divisions or coordinations within a conceptual scheme, especially:
a. Aristotle's modes of objective being, such as quality, quantity, or relation, that are inherent in all things.
b. Kant's modes of subjective understanding, such as singularity, universality, or particularity, that organize perceptions into knowledge.
c. A basic logical type of philosophical conception in post-Kantian philosophy.
a. A property or structural unit of a language, such as a part of speech or a type of phrase.
b. A specific grammatical defining property of a linguistic unit or class, such as number or gender in the noun and tense or voice in the verb.
4. Mathematics A class of objects, together with a class of morphisms between those objects, and an associative composition rule for those morphisms. Categories are used to study a wide variety of mathematical constructions in a similar way.
[French catégorie, from Old French, from Late Latin catēgoria, class of predicables, from Greek katēgoriā, accusation, charge, from katēgorein, to accuse, predicate : kat-, kata-, down, against; see CATA- + agoreuein, ēgor-, to speak in public (from agorā, marketplace, assembly; see ger- in the Appendix of Indo-European roots).]
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