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.
Other unopposed races include two for trustee on the North Shore Water Reclamation District board; two countywide posts, Clerk Anthony Vega and Regional Schools Superintendent Michael Karner; and seven County Board Dems. — Charles Selle, Chicago Tribune, 23 Sep. 2026 Republican David Graham, who ran unopposed, will be the GOP nominee for attorney general this fall. — Phillip M. Bailey, USA Today, 16 Sep. 2026 Porsche Middleton is running unopposed for the District 5 seat. — Don Sweeney, Sacbee.com, 16 Sep. 2026 Candidates running unopposed are expected to be declared winners late Monday. — ABC News, 13 Sep. 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

Browse Nearby Words

Cite this Entry

“Unopposed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unopposed. Accessed 5 Oct. 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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