Definition:Pairwise Disjoint

Definition
Let $\mathbb S$ be a set of sets such that:
 * $\forall T_1, T_2 \in \mathbb S: T_1 \cap T_2 = \varnothing$

That is, if the intersection of each pair of sets is empty.

Then the sets in $\mathbb S$ are said to be pairwise disjoint or mutually disjoint.