1. (superl.) Waste; desert; desolate; lonely.

2. (superl.) of the vast ocean; vast mountains; the vast empire of Russia.

3. (superl.) Very great in numbers, quantity, or amount; as, a vast army; a vast sum of money.

4. (superl.) Very great in importance; as, a subject of vast concern.

5. (n.) A waste region; boundless space; immensity.

Atlantean Brobdingnagian Cyclopean Gargantuan Herculean Homeric abysmal ample amplitudinous astronomic astronomical awesome behemoth big boundless broad bulky capacious colossal commodious cosmic deep elephantine endless enormous epic expansive extended extending extensive far-flung far-reaching galactic giant giantlike gigantic great heroic huge humongous immeasurable immense incalculable indeterminate inexhaustible infinite interminable jumbo king-size large limitless mammoth massive massy measureless mighty monster monstrous monumental mountainous never-ending outsize overgrown prodigious profound roomy sizable spacious spreading stupendous titanic towering tremendous unbounded unlimited voluminous weighty whopping wide widespread