Synonyms for Oppose (same or very similar meaning)
WordNet sense 1 (oppose with equal weight or force):
counterbalance
WordNet sense 2 (act against or in opposition to):
react
WordNet sense 3 (fight against or resist strongly):
defend, fight, fight back, fight down
WordNet sense 4 (set into opposition or rivalry):
match, pit
WordNet sense 5 (be resistant to):
contradict, controvert
From the ODE community, based on WordNet
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