homotopy hypothesis-theorem
delooping hypothesis-theorem
stabilization hypothesis-theorem
n-category = (n,n)-category
n-groupoid = (n,0)-category
A strict -groupoid or strict -groupoidis a strict ω-category in which all k-morphisms have a strict inverse for all
By a result by Brown and Higgins, going back to insights by Whitehead, -groupoids are equivalently modeled by crossed complexes.
Strict -groupoids form one of the vertices of the cosmic cube of higher category theory.
There is a model structure on strict ∞-groupoids.
This should present the full sub-(∞,1)-category of ∞Grpd on strict -groupoids.
A textbook reference is
The equivalence of strict -groupoids and crossed complexes is discussed in
Notice that this article says ”-groupoid” for strict globular -groupoid and ”-groupoid” for strict cubical -groupoid .