Noun

(categories)

A group, often named or numbered, to which items are assigned based on similarity or defined criteria.

*

The traditional way of describing the similarities and differences between constituents is to say that they belong to categories'' of various types. Thus, words like ''boy'', ''girl'', ''man'', ''woman'', etc. are traditionally said to belong to the category''' of Nouns, whereas words like ''a'', ''the'', ''this'', and ''that'' are traditionally said to belong to the ' category of Determiners.

This steep and dangerous climb belongs to the most difficult category .

I wouldn't put this book in the same category as the author's first novel.

(mathematics) 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.

One well-known category has sets as objects and functions as arrows.

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.

Noun

(en noun)

section

zone (designated area).

(geometry) part of a circle, extending to the center

(computing) fixed-sized unit (traditionally 512 bytes) of sequential data stored on a track of a digital medium (compare to block)

(military) an area designated by boundaries within which a unit operates, and for which it is responsible

(military) one of the subdivisions of a coastal frontier

(science fiction) a fictional region of space designated for navigational or governance purposes; for instance, ,

(calculation) an instrument consisting of two rulers of equal length joined by a hinge ^W

a field of economic activity

*{{quote-magazine, date=2013-06-28, author=(Joris Luyendijk)

, volume=189, issue=3, page=21, magazine=(The Guardian Weekly) , title= Our banks are out of control , passage=Seeing the British establishment struggle with the financial sector is like watching an alcoholic who still resists the idea that something drastic needs to happen for him to turn his life around. Until 2008 there was denial over what finance had become. When a series of bank failures made this impossible, there was widespread anger, leading to the public humiliation of symbolic figures.}}