Synonyms for Competition (same or very similar meaning)
WordNet sense 1 (the contestant you hope to defeat):
challenger, competitor, contender, rival
WordNet sense 2 (an occasion on which a winner is selected from among two or more contestants):
contest, contest
WordNet sense 3 (the act of competing as for profit or a prize):
contention, rivalry
From the ODE community, based on WordNet
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