Liberty is -- and has always been -- the properly defined exercise of freedom that does not violate the rights of others.
Your right to liberty is not violated by restrictions on your freedom to rape and murder, because you have no such right in the first place.
[spooner.org]
(Contrast with License. Compare to Equal Liberty.)
[bk]
The word 'liberty' describes all behavior that is absent coercion.
The principled rejection of aggression and coercion is the same thing as the principled support for liberty.
[bk]
No one is obliged to do more than comply with this injunction: In the exercise of your own rights do not encroach upon the rights of another; an injunction which is the exact definition of liberty.
Pierre-Joseph Proudhon, What Is Property?
[proudhon]