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
If left untreated, Lyme disease can progress to cause facial paralysis, heart rhythm abnormalities, arthritis and other serious complications.
—
Omer Awan,
Forbes.com,
23 June 2026
The cause of death was determined to be an untreated infection of the wounds.
—
Alexa Herrera,
CBS News,
23 June 2026
If left untreated, screwworm infestations can eventually kill the animal host within seven to 14 days.
—
Jen Christensen,
CNN Money,
22 June 2026
On an untreated surface, the margin between removing sulfur atoms and damaging the underlying molybdenum layer is extremely small, meaning some ions can easily cause unwanted damage.
—
Bojan Stojkovski,
Interesting Engineering,
21 June 2026
See All Example Sentences for untreated
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Omer Awan,
Forbes.com,
23 June 2026
The cause of death was determined to be an untreated infection of the wounds.
—
Alexa Herrera,
CBS News,
23 June 2026
If left untreated, screwworm infestations can eventually kill the animal host within seven to 14 days.
—
Jen Christensen,
CNN Money,
22 June 2026
On an untreated surface, the margin between removing sulfur atoms and damaging the underlying molybdenum layer is extremely small, meaning some ions can easily cause unwanted damage.
—
Bojan Stojkovski,
Interesting Engineering,
21 June 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 1 Jul. 2026.
Copy CitationMedical Definition
untreated
adjective
un·treat·ed
-ˈtrēt-əd
: not subjected to treatment
an untreated disease
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