1. Waste; desert; desolate; lonely. [Obs.]
"The empty, vast, and wandering air." -- Shak.
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.
"Through the vast and boundless deep." -- Milton.
3. Very great in numbers, quantity, or amount; as, a vast army; a vast sum of money.
4. Very great in importance; as, a subject of vast concern.
Syn. -- Enormous; huge; immense; mighty.