A company or person that is one of exactly two dominant producers or sellers in a particular market.
From duopoly + -ist (from Latin -ista, a suffix meaning 'one who practices or specializes in'). A duopolist is an actor in a duopoly market structure.
Duopolists often have an interesting relationship—they compete fiercely on marketing and features but have little incentive to actually lower prices, since both would lose money, so they're rivals who secretly benefit from each other's existence.
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