- AKA: Preorder, Quasiorder.
- See: Partial Order Relation, Order Relation, Entailment Relation.
- (Wikipedia, 2015) ⇒ http://en.wikipedia.org/wiki/Glossary_of_order_theory#P Retrieved:2015-6-14.
- (Wikipedia, 2009) ⇒ http://en.wikipedia.org/wiki/Preorder
- In mathematics, especially in order theory, preorders are binary relations that satisfy certain conditions. For example, all partial orders and equivalence relations are preorders. The name quasiorder is also common for preorders. Other names are pre-order, quasi-order, and quasi order. Many order theoretical definitions for partially ordered sets can be generalized to preorders, but the extra effort of generalization is rarely needed.