Polyad

In mathematics, polyad is a concept of category theory introduced by Jean Bénabou in generalising monads.{{Citation|last=Benabou|first=Jean|year=1967|title=Introduction to Bicategories}} A polyad in a bicategory D is a bicategory morphism Φ from a locally punctual bicategory C to D, {{nowrap|Φ : C → D}}. (A bicategory C is called locally punctual if all hom-categories C(X,Y) consist of one object and one morphism only.) Monads are polyads {{nowrap|Φ : C → D}} where C has only one object.