IPA: //ʌnˈtriːtəbl//
KK: /ʌnˈtritəbl/
Something that cannot be treated or cured.
The doctor explained that the disease was untreatable and required alternative care.
Untreatable → It is formed from "un-" (meaning not) and "treat" (from Old French *traiter*, meaning to handle or deal with) and "-able" (meaning capable of). The word "untreatable" means not capable of being handled or dealt with, often referring to a medical condition that cannot be treated.
Think of 'not' ('un-') being able to 'handle' ('traiter') something, which helps you remember that 'untreatable' means something that cannot be treated.