topological subspace
dense set
subset whose closure is the whole space
connected component
topological space
convex set
subset of an affine space that is closed under convex combinations
closure
in a topological space, the smallest closed set containing a given set
exterior
term in topology
interior
given a subset S of a topological space X, the biggest set of points in S not part of the boundary of S
nowhere dense set
mathematical set whose closure has empty interior