Definition:Reflexive Relation

Definition
Let $\mathcal R \subseteq S \times S$ be a relation in $S$. $\mathcal R$ is reflexive iff:


 * $\forall x \in S: \left({x, x}\right) \in \mathcal R$

Also see

 * Reflexivity of Relations


 * Coreflexive Relation
 * Antireflexive Relation
 * Non-reflexive Relation