untreated

adjective

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

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.
Wood Surfaces Steel wool can damage wood surfaces, especially if the wood is soft or untreated. Maria Sabella, Better Homes & Gardens, 19 June 2025 Silverplate can, however, be permanently tarnished if untreated. Daley Quinn, Southern Living, 18 June 2025 The standard is to protect infants under 6 months, who can become seriously ill and die if untreated, if exposed to high levels of nitrate, according to the EPA. Julia Jacobo, ABC News, 16 June 2025 During last year’s salmonella outbreak, the farm defended its untreated canal water, saying that it was used for underground irrigation and not applied to the edible parts of the plant. Suzy Khimm, NBC news, 7 June 2025 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

Browse Nearby Words

Cite this Entry

“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 1 Jul. 2025.

Medical Definition

untreated

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

More from Merriam-Webster on untreated

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