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.
In untreated films, bare lead atoms remain exposed on the outer boundary. — Aman Tripathi, Interesting Engineering, 3 Sep. 2026 Inspectors suspended the permit because of an untreated roach infestation at the time of inspection. — Lillie Davidson, Fort Worth Star-Telegram, 2 Sep. 2026 Currently, these small and medium textile enterprises discharge untreated wastewater from fabric dyeing directly into the ground. — Jennifer Bringle, Footwear News, 2 Sep. 2026 Do not drink untreated river water or use it to prepare food. — Zach Hillstrom, USA Today, 31 Aug. 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 7 Sep. 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
Last Updated: - Updated example sentences
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