monocentre

Monocentre is a term that describes the presence of a single central point in a system or object. The word is formed from mono- meaning one and centre meaning central point; in British English the spelling monocentre is common, while monocenter appears in American English.

In geometry and related fields, monocentre is used in some texts to refer to a unique center from which certain properties are defined. For example, a circle or a sphere has a single center, which can be described as its monocentre. More generally, a monocentric configuration is one in which all relevant distances, radii, or symmetries are referenced to this single point. However, the term is not universally used in contemporary textbooks, where terms such as center, circumcenter, or focal point are more common.

In urban planning and geography, monocentre (or monocentric) describes a city or region in which a single core concentrates most employment, services, and housing, typically around a central business district. This contrasts with polycentric forms, where multiple centers exist and function as hubs.

Outside of these domains, monocentre may be used adjectivally to describe any system characterized by a single central hub. Because the precise meaning varies by field, researchers usually define monocentre explicitly when introducing it.