Collectionwise normal space

Symbol-free definition
A topological space is termed collectionwise normal if it is T1 and, given any discrete collection of closed sets (viz., a disjoint collection of closed sets such that the union of any subcollection is closed), there exists a family of pairwise disjoint open sets containing each of the closed sets.

Stronger properties

 * Weaker than::Metrizable space
 * Weaker than::Elastic space
 * Weaker than::Linearly orderable space
 * Weaker than::Monotonically normal space
 * Weaker than::Hereditarily collectionwise normal space

Weaker properties

 * Stronger than::Normal space
 * Stronger than::Collectionwise Hausdorff space