Is usually an accusation made by someone in regards to another person's use of a word. Sometimes it is valid, as in when a person is using a word in a way that is different or contrary to a accepted usage.
An example of this might well be the wayfree will is used in this node about predestination. Usually free will means a choice of outcomes, where as predestination means a person is absoluely going to go to heaven or hell.
It also comes up when there is a misunderstanding over a word having multiple meanings. Example:
Communistic, which can mean a utopian society where all is owned in common for the common good. However it also can be correctly used to mean a totalitarian socialist society. This is because language evolves, words acquire new connotations and eventually definitions through use. Though they were not truly communist the Soviet Union used it to describe themselves and so the word became associated with their style of governance.
An awful lot of political disagreements could be diffused if the debaters would discuss their different perceptions of words. Rather than just accusing each other of arbitrary redefinition of words or generally being the antichrist. Though there is also probably some willful ignoring of other definitions or common usage for political reasons.
See also: The Use of Cracker vs. Hacker | 
