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

Synonyms of untreated

• crude
• unprocessed
• natural
• raw
• native

Examples of untreated in a Sentence

untreated wool

Recent Examples on the Web

And in Madagascar, textile factories and industrial parks have been accused of skirting water-treatment requirements and releasing untreated or partially treated wastewater into waterways. — Jasmin Malik Chua, Footwear News, 29 Sep. 2026

These rodents also performed better on standard memory tests than their untreated counterparts, even though both groups had similar levels of tau. — Amanda Erickson, STAT, 29 Sep. 2026

This controversial bill will cause 15 million Americans to lose their insurance coverage and eventually result in 50,000 additional deaths a year as many manageable conditions are left untreated. — Dr. Michael Good, Hartford Courant, 28 Sep. 2026

The microscopic structures increased the surface area available for lithium deposition to around four times that of untreated flat copper foil. — Atharva Gosavi, Interesting Engineering, 22 Sep. 2026

Word History

First Known Use

15th century, in the meaning defined above

Rhymes for untreated

• accreted
• competed
• completed
• conceited
• concreted
• defeated
• deleted
• depleted
• entreated
• intreated
• maltreated
• mistreated

Medical Definition

untreated

adjective

un·​treat·​ed -ˈtrēt-əd 

: not subjected to treatment

an untreated disease