Neighbourhood
From Encyclopedia of Mathematics
of a point 
(of a subset 
) of a topological space
Any open subset of this space containing the point 
(the set 
). Sometimes a neighbourhood of the point 
(the set 
) is defined as any subset of this topological space containing the point 
(the set 
) in its interior (cf. also Interior of a set).
How to Cite This Entry:
Neighbourhood. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Neighbourhood&oldid=30570
Neighbourhood. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Neighbourhood&oldid=30570
This article was adapted from an original article by B.A. Pasynkov (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article