Unusually great in size or amount or degree or especially extent or scope:
— At vast (or immense) expense.
— The vast reaches of outer space.
— The vast accumulation of knowledge...which we call civilization.

synonyms: Brobdingnagian, huge, immense.

Roget 31: great; greater etc. 33; large, considerable, fair, above par; big, huge etc. (large in size) 192; Herculean, cyclopean; ample; abundant; etc. (enough) 639 full, intense, strong, sound, passing, heavy, plenary, deep, high; signal, at its height, in the zenith.    world-wide, widespread, far-famed, extensive; wholesale; many etc. 102.    goodly, noble, precious, mighty; sad, grave, heavy, serious; far gone, arrant, downright; utter, uttermost; crass, gross, arch, profound, intense, consummate; rank, uninitiated, red-hot, desperate; glaring, flagrant, stark staring; thorough-paced, thoroughgoing; roaring, thumping; extraordinary.   ; important etc. 642; unsurpassed etc. (supreme) 33; complete etc. 52.    august, grand, dignified, sublime, majestic etc. (repute) 873.    vast, immense, enormous, extreme; inordinate, excessive, extravagant, exorbitant, outrageous, preposterous, unconscionable, swinging, monstrous, overgrown; towering, stupendous, prodigious, astonishing, incredible; marvelous etc. 870.    unlimited etc. (infinite) 105; unapproachable, unutterable, indescribable, ineffable, unspeakable, inexpressible, beyond expression, fabulous.    undiminished, unabated, unreduced^†, unrestricted.    absolute, positive, stark, decided, unequivocal, essential, perfect, finished.    remarkable, of mark, marked, pointed, veriest; noteworthy; renowned.    ... show more

Roget 180: spacious, roomy, extensive, expansive, capacious, ample; widespread, vast, world-wide, uncircumscribed; boundless etc. (infinite) 105; shoreless^†, trackless, pathless; extended.    ... show more

Roget 192: large, big; great etc. (in quantity) 31; considerable, bulky, voluminous, ample, massive, massy; capacious, comprehensive; spacious etc. 180; mighty, towering, fine, magnificent.    corpulent, stout, fat, obese, plump, squab, full, lusty, strapping, bouncing; portly, burly, well-fed, full-grown; corn fed, gram fed; stalwart, brawny, fleshy; goodly; in good case, in good condition; in condition; chopping, jolly; chub faced, chubby faced.    lubberly, hulky, unwieldy, lumpish, gaunt, spanking, whacking, whopping, walloping, thumping, thundering, hulking; overgrown; puffy etc. (swollen) 194.    huge, immense, enormous, mighty; vast, vasty; amplitudinous, stupendous; monster, monstrous, humongous, monumental; elephantine, jumbo, mammoth; gigantic, gigantean, giant, giant like, titanic; prodigious, colossal, Cyclopean, Brobdingnagian, Bunyanesque, Herculean, Gargantuan; infinite etc. 105.    large as life; plump as a dumpling, plump as a partridge; fat as a pig, fat as a quail, fat as butter, fat as brawn, fat as bacon.    immeasurable, unfathomable, unplumbed; inconceivable, unimaginable, unheard-of.    of cosmic proportions; of epic proportions, the mother of all, teh granddaddy of all.    ... show more