Any action in opposition to a previous action.
An act of retaliation; a counterattack
Actions by one political group against another political group, either by using governmental power or by popular actions such as protests; generally, disagreement in politics.
A recognized political party or group of parties in multiparty political systems that is present in Parliament or some other legislative body and does not control the floor (usually due to being in the minority).
An unrecognized political party in a one-party state.