Definition:Quasi-Reflexive Relation/Definition 2

Definition
Let $\RR \subseteq S \times S$ be a relation in $S$.

$\RR$ is quasi-reflexive :


 * $\forall x \in \map {\mathrm {Field} } \RR: \tuple {x, x} \in \RR$

where $\map {\mathrm {Field} } \RR$ denotes the field of $\RR$.

Also see

 * Equivalence of Definitions of Quasi-Reflexive Relation