archrival

/ˈɑːrtʃˌraɪvəl/
noun
  1. A person's or group's main competitor or enemy, often in sports, business, or other competitive fields.
    • Her archrival in the spelling bee had won the competition three years in a row.
    • In the tech industry, the two companies are archrivals, always trying to outdo each other.
    • The two soccer teams have been archrivals for over a hundred years.
Antonyms
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