Partial groupoid

Group-like structures
Total Associative Identity Divisible
Partial magma UnneededUnneededUnneededUnneeded
Multiplicative UnneededUnneededRequiredUnneeded
Semigroupoid UnneededRequiredUnneededUnneeded
Small category UnneededRequiredRequiredUnneeded
Groupoid UnneededRequiredRequiredRequired
Magma RequiredUnneededUnneededUnneeded
Quasigroup RequiredUnneededUnneededRequired
Unital magma RequiredUnneededRequiredUnneeded
Loop RequiredUnneededRequiredRequired
Semigroup RequiredRequiredUnneededUnneeded
Associative quasigroup RequiredRequiredUnneededRequired
Monoid RequiredRequiredRequiredUnneeded
Group RequiredRequiredRequiredRequired

In abstract algebra, a partial groupoid (also called halfgroupoid, pargoid, or partial magma) is a set endowed with a partial binary operation.

A partial groupoid is a partial algebra.