"invariant" - key terms from Wikipedia

adiabatic invariant
conformally invariant
dickson invariant
gauge invariant
geometric invariant	theory
graph invariant
invariant
invariant	chain
invariant	mass
invariant	measure
invariant	set
invariant	subspace
invariant	subspace problem
invariant	theory
invariant	under
left invariant
loop invariant
lorentz invariant
scale invariant
time invariant
translation invariant