uncombustible

English

Etymology

From un- +‎ combustible.

Adjective

uncombustible (comparative more uncombustible, superlative most uncombustible)

1. Synonym of incombustible
   • 1967, United States. Congress. House. Appropriations, Second Supplemental Appropriation Bill: 1967, Hearings..., page 279:

     You also have trash which is uncombustible, such as bedsprings, cans, and other metal objects?