Any word and/or concept can be defined and redefined at will. They are
just symbols which carry whatever meaning *we* want!
Thus, anarchists define anarchism in a specific way, which most of the
time is very different to the way dictionaries define it. But this is
the pleasure of a good conversation, to dig through labels and see what
they really relate to.
Dictionaries are the cemeteries of our living words :)
(in Greece, the very word "democracy" might have been used almost as in
injure, technically it should/could have been called "demarchy". See http://en.wikipedia.org/wiki/Athenian_democracy )