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

• crude
• native
• natural
• raw
• rude
• undressed
• unprocessed
• unrefined

Examples of untreated in a Sentence

untreated wool

Recent Examples on the Web

Those who leave chronic hepatitis B untreated have a 25% to 40% risk of developing liver cancer at some point in their lives, according to the Hepatitis B Foundation. —Hannah Yasharoff, USA Today, 1 May 2025

If left untreated, both conditions can lead to serious health consequences. —Danielle Weiss, Verywell Health, 30 Apr. 2025

Borges had been eligible for parole years ago but had been denied the benefit despite staging hunger strikes and developing several health ailments, including untreated cataracts that affected his vision. —Nora Gámez Torres, Miami Herald, 25 Apr. 2025

Also, there are some mattresses using untreated polyester and, believe it or not, Kevlar, and fiberglass. —Beth Ann Mayer, Parents, 23 Apr. 2025

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