Two groups 
and 
are said to be isoclinic if there are isomorphisms 
and 
, where 
is the group center of
the group, which identify the two commutator maps.
Isoclinic Groups
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References
Conway, J. H.; Curtis, R. T.; Norton, S. P.; Parker, R. A.; and Wilson, R. A. "Isoclinism." §6.7 in Atlas of Finite Groups: Maximal Subgroups and Ordinary Characters for Simple Groups. Oxford, England: Clarendon Press, pp. xxiii-xxiv, 1985.Referenced on Wolfram|Alpha
Isoclinic GroupsCite this as:
Weisstein, Eric W. "Isoclinic Groups." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/IsoclinicGroups.html