Definition:Closed Linear Subspace

Definition
Let $V$ be a topological vector space.

A linear subspace of $V$ that is closed is called a closed linear subspace.

Also see

 * Vector Subspace
 * Closed Linear Span, a commonly encountered closed linear subspace
 * Closed Linear Subspaces Closed under Intersection
 * Closed Linear Subspaces Closed under Setwise Addition