Vast (v&adot_;st), a. [Compar. Vaster (v&adot_;st&etilde_;r); superl. Vastest.] [L. vastus empty, waste, enormous, immense: cf. F. vaste. See Waste, and cf. Devastate.]
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1. Waste; desert; desolate; lonely. [Obs.]
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The empty, vast, and wandering air. Shak.
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2. Of great extent; very spacious or large; also, huge in bulk; immense; enormous; as, the vast ocean; vast mountains; the vast empire of Russia.
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Through the vast and boundless deep. Milton.
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3. Very great in numbers, quantity, or amount; as, a vast army; a vast sum of money.
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4. Very great in force; mighty; as, vast labor.
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5. Very great in importance; as, a subject of vast concern.
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Syn. -- Enormous; huge; immense; mighty.
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