Category definition, any general or comprehensive division; a class. See more.But for the whole of the day, there is no disguising it, you must put yourself in the same category with Mrs.The cars belong to the same category. Taxpayers fall into one of several categories. She competed for the award in her age category.Synonyms for category at Thesaurus.com with free online thesaurus, antonyms, and definitions. Dictionary and Word of the Day.pl.-·ries. a class or division in a scheme of classification; Logic any of the various basic concepts into which all knowledge can be classified; Origin of categoryIn mathematics, a category is an algebraic structure that comprises “objects” that are linked by “arrows”. A category has two basic properties: the ability to compose Category. A category consists of three things: a collection of objects, for each pair of objects a collection of morphisms (sometimes call “arrows”) from one to The traditional way of describing the similarities and differences between constituents is to say that they belong to categories of various types.Categories provide a helpful way to group related posts together, and to quickly tell readers what a post is about. Categories also make it easier for people to find Seen and Heard. What made you want to look up category? Please tell us where you read or heard it (including the quote, if possible).