A group action of a group 
on a set 
is semiregular if no group element
other than the identity element fixes a point
of 
.
Equivalently, this means that the stabilizer of every
point of 
is trivial. A group acting this way is sometimes called a semiregular group on 
.
A semiregular group action need not be transitive.
A semiregular group action that is also transitive is a regular
group action.
Semiregular Group Action
See also
Group Action, Group Orbit, Regular Group Action, Stabilizer, Transitive Group ActionExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Semiregular Group Action." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/SemiregularGroupAction.html