Isoclinic Groups
Two Groups 
and 
are said to be isoclinic if there are isomorphisms 
and 
,where 
is the Center of the group, which identify the two commutator maps.
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.
- Lemniscate of Bernoulli
- Lemniscate of Gerono
- Lemoine Axis
- Lemoine Circle
- Lemoine Line
- Lemoine Point
- Lemoine's Problem
- Lemon
- Length (Curve)
- Length Distribution Function
- Length (Number)
- Length (Partial Order)
- Length (Size)
- Lengyel's Constant
- Lens
- Lens Space
- Lenstra Elliptic Curve Method
- Leonardo's Paradox
- Leptokurtic
- Lerch's Theorem
- Lerch Transcendent
- Less
- L-Estimate
- Letter-Value Display
- Leudesdorf Theorem