semi-closed

Definition

• Let (X, τ) be a topological space. A subset S ⊆ X is called semi-closed if the complement X-B is a semi-open set.

Reference

• Bhattacharyya Paritosh, Lahiri B. K., Semigeneralized closed sets in topology., Indian J. Math. 29 (1987), no. 3, 375-382 (1988).