oppositional Definition

1. The act of resisting or fighting against someone or something by force or argument.

Thesaurus: antagonism, hostility, protest, resistance, defiance, malice, hate, dislike, defiance, antipathy, aversion, anger; Antonym: support.
2. The state of being hostile or in conflict.

Thesaurus: hostilities, contention, fighting, conflict, clashing, combat, warfare, rivalry; Antonym: peace.
3. A person or group of people who are opposed to something.

Thesaurus: rival, the other side, opponent.
4. A political party which opposes the party in power. Also (opposition) as adj.

Form: the Opposition (usually)
5. An act of opposing or being placed opposite.
6. logic.
A difference of quantity or quality between two propositions with the same subject and predicate.
7. astron.astrol.
The position of a planet or star when it is directly opposite another, especially the Sun, as seen from the Earth.