duopoly
noun
du·op·o·ly du̇-ˈä-pə-lē 
also dyu̇-
plural duopolies
1
: an oligopoly limited to two sellers
2
: preponderant influence or control by two political powers
duopolistic
d(y)u̇-ˌä-pə-ˈli-stik
adjective 
Example Sentences
Recent Examples on the Web Various regulatory bodies have forced the Google/Apple app store duopoly to open up payments, but Google and Apple have each done so without fixing the core problem of high app store fees. 
Ron Amadeo, Ars Technica, 2 Sep. 2022 Efforts are slowly trickling to break through the duopoly. al, 14 Aug. 2022 The two largest firms (ISS and Glass Lewis) control 97 percent of the proxy advisory market – effectively, the proxy advisory market is controlled by a duopoly. Wayne Winegarden, Forbes, 25 July 2022 But even in the era of their duopoly, the 2022-23 season, which begins on Friday, is unlike any in the history of English soccer. Joshua Robinson, WSJ, 4 Aug. 2022 Every company that wants to provide search to the world faces either a duopoly or a very long journey. Kevin Purdy, Ars Technica, 5 Aug. 2022 Yet more than a third of the voters wanted to opt out of the two-party duopoly in the misguided belief that an overconfident billionaire could save the nation. Walter Shapiro, The New Republic, 27 June 2022 The Amazon-Flipkart duopoly is fast becoming a four-way competition as Reliance Digital and Tata join the fray, signaling tougher local competition in the future. Megha Mandavia, WSJ, 3 May 2022 There’s a certain irony to the fact that the key to breaking our political duopoly and returning some modicum of sanity to our politics could actually come from heavily blue or red states. Garry Kasparov, CNN, 26 Apr. 2022 See More
Ron Amadeo, Ars Technica, 2 Sep. 2022 Efforts are slowly trickling to break through the duopoly. al, 14 Aug. 2022 The two largest firms (ISS and Glass Lewis) control 97 percent of the proxy advisory market – effectively, the proxy advisory market is controlled by a duopoly. Wayne Winegarden, Forbes, 25 July 2022 But even in the era of their duopoly, the 2022-23 season, which begins on Friday, is unlike any in the history of English soccer. Joshua Robinson, WSJ, 4 Aug. 2022 Every company that wants to provide search to the world faces either a duopoly or a very long journey. Kevin Purdy, Ars Technica, 5 Aug. 2022 Yet more than a third of the voters wanted to opt out of the two-party duopoly in the misguided belief that an overconfident billionaire could save the nation. Walter Shapiro, The New Republic, 27 June 2022 The Amazon-Flipkart duopoly is fast becoming a four-way competition as Reliance Digital and Tata join the fray, signaling tougher local competition in the future. Megha Mandavia, WSJ, 3 May 2022 There’s a certain irony to the fact that the key to breaking our political duopoly and returning some modicum of sanity to our politics could actually come from heavily blue or red states. Garry Kasparov, CNN, 26 Apr. 2022 See More Word History
Etymology
duo- + -poly (as in monopoly)
First Known Use
1920, in the meaning defined at sense 1