Same word as vaster:

all-inclusive, ample, astronomical, big, boundless, broad, capacious, colossal, comprehensive, detailed, endless, enormous, eternal, expanded, extensive, far-flung, far-reaching, forever, giant, gigantic, great, huge, illimitable, immeasurable, immense, infinite, limitless, mammoth, massive, measureless, monstrous, monumental, never-ending, prodigious, prolonged, spacious, spread-out, stretched-out, sweeping, titanic, tremendous, unbounded, unlimited, voluminous, widespread