An -group is a group object internal to n-groupoids.
If it is deloopable, an -group is the hom-object of an n-groupoid with a single object .
If is a strict n-groupoid, then the corresponding -group is called strict. Strict -groups are equivalent to crossed complexes of groups, of length .
Under the homotopy hypothesis -groups correspond to (pointed) connected homotopy n-types.
See also