Definition:Entourage
From ProofWiki
Definition
Let $S$ be a set and let $\mathcal U \subseteq \mathcal P \left({S \times S}\right)$ be a quasiuniformity on $S$.
An element $u \in \mathcal U$ of such a quasiuniformity is known as an entourage (or relation) of $\mathcal U$.
Note that an entourage of $\mathcal U$ actually is a relation on $S$.
Linguistic Note
The word entourage is a French one, meaning neighborhood or surroundings.
In (natural language) English the word has come to mean the people one surrounds oneself with, usually in the context of celebrity lifestyles (although I learn that it became the fashionable term for posse or gang among pretentious teenagers in the early 2010's).
Sources
- Lynn Arthur Steen and J. Arthur Seebach, Jr.: Counterexamples in Topology (1970)... (previous)... (next): $\text{I}: \ \S 5$: Uniformities
