Definition of "Opposition" :

noun: the action of opposing something that you disapprove or disagree with

"Despite opposition from the newspapers he went ahead."

noun: the act of hostile groups opposing each other

"The invaders encountered stiff opposition."

noun: a body of people united in opposing something

noun: the major political party opposed to the party in office and prepared to replace it if elected

"Her Majesty's loyal opposition."

noun: an armed adversary (especially a member of an opposing military force)

noun: a contestant that you are matched against

noun: a direction opposite to another

noun: the relation between opposed entities