A topological space 
in which each subset of 
of the "first category" has an empty interior. A
topological space which is homeomorphic
to a complete metric space is a Baire space.
Baire Space
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Cite this as:
Weisstein, Eric W. "Baire Space." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/BaireSpace.html