THESAURUS
cavernous
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, 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
ROGET THESAURUS
cavernous
Concavity
N
concavity, depression, dip, hollow, hollowness, indentation, intaglio, cavity, dent, dint, dimple, follicle, pit, sinus, alveolus, lacuna, excavation, strip mine, trough, honeycomb, cup, basin, crater, punch bowl, cell, socket, valley, vale, dale, dell, dingle, combe, bottom, slade, strath, glade, grove, glen, cave, cavern, cove, grot, grotto, alcove, cul-de- sac, gully, arch, bay, excavator, sapper, miner, honeycomb (sponge), depressed, alveolate, calathiform, cup-shaped, dishing, favaginous, faveolate, favose, scyphiform, scyphose, concave, hollow, stove in, retiring, retreating,
cavernous, porous, infundibul, infundibular, infundibuliform, funnel shaped, bell shaped, campaniform, capsular, vaulted, arched.
Rarity
N
rarity, tenuity, absence of solidity, subtility, subtilty, subtlety, sponginess, compressibility, rarefaction, expansion, dilatation, inflation, subtilization, vaporization, evaporation, diffusion, gassification, ether, rare, subtile, thin, fine, tenuous, compressible, flimsy, slight, light,
cavernous, spongy, rarefied, unsubstantial, uncompact, incompressed, rarefiable.