Definition of CATEGORY

category

Plural: categories

Noun

  • A class or division in a system of classification.
  • a collection of things sharing a common attribute
  • a general concept that marks divisions or coordinations in a conceptual scheme
  • A group, often named or numbered, to which items are assigned based on similarity or defined criteria.
  • A collection of objects, together with a transitively closed collection of composable arrows between them, such that every object has an identity arrow, and such that arrow composition is associative.

Examples

  • His strategy falls into the ’risky but rewarding’ category of Scrabble plays.
  • I wouldn’t put this book in the same category as the author’s first novel.
  • Just as a monoid consists of an underlying set with a binary operation "on top of it" which is closed, associative and with an identity, a category consists of an underlying digraph with an arrow composition operation "on top of it" which is transitively closed, associative, and with an identity at each object. In fact, a category's composition operation, when restricted to a single one of its objects, turns that object's set of arrows (which would all be loops) into a monoid.
  • One well-known category has sets as objects and functions as arrows.
  • This steep and dangerous climb belongs to the most difficult category.

Origin / Etymology

Late Middle English, borrowed from French catégorie, from Middle French categorie, from Late Latin catēgoria (“class of predicables”), from Ancient Greek κατηγορία (katēgoría, “head of predicables”). Doublet of categoria.

Scrabble Score: 14

category: valid Scrabble (US) TWL Word
category: valid Scrabble Word in Merriam-Webster MW Dictionary
category: valid Scrabble Word in International Collins CSW Dictionary

Words With Friends Score: 15

category: valid Words With Friends Word