If a map 
from a group 
to a group 
satisfies 
for all 
, then 
is said to be an antihomomorphism.
Antihomomorphism
See also
AntiautomorphismExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Antihomomorphism." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Antihomomorphism.html