untreated
adjective
un·treat·ed
ˌən-ˈtrē-təd 
: 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
Towns along the lower river have expressed concern that, untreated, hydrilla could reverse 70 years of environmental progress that has made the river a $1 billion contributor to the state economy.
—
Edmund H. Mahony, Hartford Courant, 14 Mar. 2026
These species can find refuge in untreated corners, then spread again once eradication and prevention efforts let up.
—Shi En Kim, AZCentral.com, 13 Mar. 2026
Therefore, any leftover water on untreated surfaces will ice up.
—Terry Eliasen, CBS News, 12 Mar. 2026
When left untreated, Sjögren’s disease can significantly impair someone’s quality of life and cause a lot of discomfort.
—Helen Carefoot, Flow Space, 12 Mar. 2026
See All Example Sentences for untreated
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Edmund H. Mahony, Hartford Courant, 14 Mar. 2026
These species can find refuge in untreated corners, then spread again once eradication and prevention efforts let up.
—Shi En Kim, AZCentral.com, 13 Mar. 2026
Therefore, any leftover water on untreated surfaces will ice up.
—Terry Eliasen, CBS News, 12 Mar. 2026
When left untreated, Sjögren’s disease can significantly impair someone’s quality of life and cause a lot of discomfort.
—Helen Carefoot, Flow Space, 12 Mar. 2026
See All Example Sentences for untreated
Cite this Entry
“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 16 Mar. 2026.
Copy CitationMedical Definition
untreated
adjective
un·treat·ed
-ˈtrēt-əd
: not subjected to treatment
an untreated disease
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