monumentalPronunciation: /mɒnjʊˈmɛnt(ə)l/Translate monumental | into German | into Italian | into Spanish Definition of monumental adjective 1great in importance, extent, or size:it’s been a monumental effort 2of or serving as a monument:additional details are found in monumental inscriptionsDerivatives monumentalityPronunciation: /-ˈtalɪti/ noun monumentally adverb monumental in other Oxford dictionaries Definition of monumental in the US English dictionary