Cavernous

Adjective

 * 1) resembling a cavern; vast
 * 2) having many caverns

Adverbs for Cavernous
darkly; dimly; vastly; mysteriously; allur; deeply; dangerously; alarmingly; irresistibly; fantastically; gloomily; obscurely; duskily; murkily; sombrely; astonishingly; marvellously; frighteningly; indistinctly; strangely; terribly; hideously; formidably; awfully.

Thesaurus
hollowed, incurved, incurving, incurvous, infundibular, infundibuliform, navicular, naviform, plumbless, plunging, retiring, retreating, reverberant, saucer-shaped, scaphoid, scyphate, sepulchral, soundless, spoonlike, sunk, sunken, unfathomable, unfathomed, unsounded, vast, without bottom, yawning, abysmal, abyssal, boat-shaped, boatlike, bottomless, bowl-shaped, bowllike, cavelike, commodious, concave, concaved, craterlike, cup-shaped, cupped, cymbiform, deep as hell, dish-shaped, dished, dishing, dishlike, fathomless, funnel-breasted, funnel-chested, funnel-shaped, gaping, hollow,