(ˈ)i(m)+ adjective
Etymology: Late Latin immitigabilis, from Latin in- in- (I) + mitigare to mitigate + -abilis -able — more at mitigate
: not capable of being mitigated, softened, lessened, or appeased
such immitigable evil
• im·mitigableness “+ noun -es
• im·mitigably “+ adverb