untreated

adjective

un·​treat·​ed ˌən-ˈtrē-təd How to pronounce untreated (audio)
Synonyms of untreatednext
: not treated
untreated wastewater
especially : not improved or controlled medically
an untreated case of pneumonia
untreated diabetic patients

Synonyms of untreated

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Examples of untreated in a Sentence

untreated wool
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.
Squamous cell carcinoma is the second most common, but unlike basal cell, this skin cancer can spread if untreated. — Norah O'Donnell, CBS News, 21 Oct. 2026 Johns Hopkins warns that untreated dry eye can cause corneal abrasions, infection or scarring that permanently affects vision. — Samantha Agate, Charlotte Observer, 21 Oct. 2026 Lamberth, who was nominated to the bench by President Ronald Reagan, pointed out that untreated gender dysphoria can cause severe side effects like depression, anxiety and suicidal thoughts. — ABC News, 21 Oct. 2026 Over time, untreated inflammation may cause scarring, narrowing of the vaginal opening or changes to the labia and clitoral hood. — Emily Cegielski, Flow Space, 20 Oct. 2026 See All Example Sentences for untreated

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of untreated was in the 15th century

Rhymes for untreated

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Browse Nearby Words

untreatable
untreated
untremulous
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Cite this Entry

“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 27 Oct. 2026.

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Medical Definition

untreated

adjective
un·​treat·​ed -ˈtrēt-əd How to pronounce untreated (audio)
: not subjected to treatment
an untreated disease
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