The closure of a set is the smallest closed set containing . Closed sets are closed under arbitrary intersection, so it is also the intersection of all closed sets containing . Typically, it is just with all of its accumulation points.

# Topological Closure

## See also

Closed Set, Sequence, Set Closure, Topology
*This entry contributed by Todd
Rowland*

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## Cite this as:

Rowland, Todd. "Topological Closure." From *MathWorld*--A Wolfram Web Resource, created by Eric
W. Weisstein. https://mathworld.wolfram.com/TopologicalClosure.html