Definition:Group Epimorphism

Definition
Let $\left({G, \circ}\right)$ and $\left({H, *}\right)$ be groups.

Let $\phi: G \to H$ be a (group) homomorphism.

Then $\phi$ is a group epimorphism iff $\phi$ is a surjection.

Also see

 * Definition:Epimorphism (Abstract Algebra)