1
: not opposed
an unopposed invasion
: having no opponent
a politician who is running for election unopposed
2
medical : being or relating to estrogen replacement therapy in which a progestin (such as medroxyprogesterone acetate) is not coadministered to reduce the potential risks (such as endometrial cancer) associated with estrogen used alone
A woman who has had her uterus removed can take the estrogen "unopposed"—that is, without the addition of progestin.Consumer Reports

Examples of unopposed in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Spurs nearly went down twice in the last two seasons, despite winning the Europa, Palace won the Conference league despite finishing 15th, and Villa won the Europa nearly unopposed, other than their semi against Forest, who finished 16th. Nnamdi Onyeagwara, New York Times, 13 July 2026 Farage will hope the by-election will return him to parliament all but unopposed, his mandate renewed and his image as a man of the people capable of taking on the system, more Teflon-coated than ever. Melissa Bell, CNN Money, 8 July 2026 Neither Carol Ammons, who was first elected to the Illinois House in 2014 and is running unopposed for a seventh term in November, nor Aaron Ammons could be reached Wednesday for comment. Olivia Olander, Chicago Tribune, 8 July 2026 Incumbent Evans, of Mexican descent, ran unopposed in the Republican primary. Saige Miller, NPR, 1 July 2026 See All Example Sentences for unopposed

Word History

First Known Use

1625, in the meaning defined at sense 1

Time Traveler
The first known use of unopposed was in 1625

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Cite this Entry

“Unopposed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unopposed. Accessed 20 Jul. 2026.

Medical Definition

unopposed

adjective
: being or relating to estrogen replacement therapy in which a progestin (as medroxyprogesterone acetate) is not coadministered to reduce the potential risks (as endometrial cancer) associated with estrogen used alone
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