monumental

1 large and impressive in size, grandeur, extent, or conception a monumental misunderstanding that had far-reaching consequences Synonyms august, baronial, epic, gallant, glorious, grandiose, heroic (also heroical), Homeric, imperial, imposing, magnific, magnificent, majestic, massive, grand, noble, proud, regal, royal, splendid, statelyRelated Words colossal, monstrous, prodigious, stupendous, tremendous; kingly, lordly, princely, queenly; awesome, awful, cosmic (also cosmical), sublime, wondrous; formidable, impressive, prepossessing, redoubtable; apocalyptic (also apocalyptical), inflated, operatic, overblown, pompous; marvelous (or marvellous), superb, terrific, wonderful; extravagant, lavish, luxurious, opulent, palatial, palatine, sumptuous; gorgeous, resplendent, splendiferous; extraordinary, killer, remarkable, sensational, striking; celestial, divine, heavenlyNear Antonyms lowly, modest, unprepossessing; average, common, mediocre, ordinary, run-of-the-mill, second-rate; abject, mean, meretricious, shabby, sordid; insignificant, measly, paltry, petty, puny, trifling, trivialAntonyms humble, unheroic, unimposing, unimpressive

2 unusually large serves a monumental sundae that usually requires three people to finish it Synonyms astronomical (also astronomic), Brobdingnagian, bumper, colossal, cosmic (also cosmical), cyclopean, elephantine, enormous, galactic, gargantuan, giant, gigantesque, gigantic, grand, herculean, heroic (also heroical), Himalayan, humongous (also humungous), immense, jumbo, king-size (or king-sized), leviathan, mammoth, massive, mega, mighty, monster, monstrous, huge, mountainous, oceanic, pharaonic, planetary, prodigious, super, super-duper, supersize, supersized, titanic, tremendous, vast, vasty, walloping, whacking, whoppingRelated Words big, bulky, considerable, extensive, good, goodly, great, gross, handsome, hefty, hulking, largish, major, outsize (also outsized), overgrown, oversize (or oversized), sizable (or sizeable), substantial, tidy, voluminous; august, formidable, grandiose, imposing, lofty, majestic; cavernous, monolithic, overwhelming, staggering, stupendous, towering; boundless, immeasurable, infiniteNear Antonyms little, mini, petite, pint-size (or pint-sized), puny, small, smallish, undersized (also undersize); dinky, dwarfish, half-pintAntonyms bantam, bitty, diminutive, infinitesimal, Lilliputian, little bitty, micro, microminiature, microscopic (also microscopical), midget, miniature, minuscule, minute, pocket, pygmy, teensy, teensy-weensy, teeny, teeny-weeny, tiny, wee

3 having great meaning or lasting effect the moon landing was seen as a monumental event in human history Synonyms big, consequential, earthshaking, earth-shattering, eventful, historic, major, material, meaningful, momentous, important, much, significant, substantial, tectonic, weightyRelated Words decisive, fatal, fateful, strategic; earnest, grave, heavy, serious, sincere; distinctive, exceptional, impressive, outstanding, prominent, remarkable; valuable, worthwhile, worthy; distinguished, eminent, great, illustrious, noble, notable, noteworthy, outstanding, preeminent, prestigious; famous, notorious, renowned; all-important, central, critical, crucial, essential, key, pivotal, seminal, vitalNear Antonyms paltry, petty, worthless; anonymous, nameless, obscure, uncelebrated, unknownAntonyms inconsequential, inconsiderable, insignificant, little, minor, negligible, slight, small, trifling, trivial, unimportant