Dissident: Non-conformist; opponent
of the existing establishment.
The term 'dissident' got
well-known in the 20th Century in connection with opponents of the
regime in the Soviet-Union and its satellite states, and in communist
China, but it seems likely that any political régime or religious belief
has its dissidents, both internally and externally.
Consequently, it is difficult to say much about dissidents in
general, except this: Wherever it is dangerous to differ in opinion from
the powers that be, there are few real dissidents.