I have a naive question on group theory, which I'm not familiar with in any detail.
Let $H<G$ be a subgroup of some group $G$. Let $g\in G$, $g\not\in H$, but $g^n\in H$ for some $n\geq 2$.
Does there exist a notion of a cyclic subgroup generated by $g$, i.e. $\{g^k|k=0,\dots, n-1\}$, in which $g^n$ is identified with the identity?
The element $g$ is not necessarily a torsion element of $G$.