oppose

Concise Oxford English Dictionary © 2008 Oxford University Press:
oppose/əˈpəʊz/

▶verb

• 1 (also be opposed to) disapprove of, resist, or be hostile to.

  ■ compete with or fight.

• 2 (as adj. opposed) (of two or more things) contrasting or conflicting.

• 3 (as adj. opposing) opposite.

– derivatives
opposer noun.

– origin ME: from OFr. opposer, from L. opponere (see opponent).