political opposition

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A recognized political party that is present in Parliament or some other legislative party and does not control the floor (usually due to being in the minority).
• noun An unrecognized political party in a one-party state.
• noun Actions by one political group against another political group, either by using governmental power or by popular actions such as protests.
• noun A more general case of disagreement in politics.