T1 space
TOPOLOGICAL SPACE IN WHICH ALL SINGLETON SETS ARE CLOSED
Accessible space; R0 space; T1 topology; Accessible topology; Frechet topology; Fréchet topology; R0 topology; Symmetric topology; T1 Space; T1-space; T1-separation axiom; T1 separation axiom; T₁ space; T1 axiom
In topology and related branches of mathematics, a T1 space is a topological space in which, for every pair of distinct points, each has a neighborhood not containing the other point.Arkhangel'skii (1990).