tectonic

having great meaning or lasting effect a tectonic shift in societal trends occurred in the 1960s Synonyms big, consequential, earthshaking, earth-shattering, eventful, historic, major, material, meaningful, momentous, monumental, much, significant, substantial, important, 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