boat-shaped, boatlike, bowl-shaped, bowllike, cavelike, cavernous, concave, concaved, craterlike, cup-shaped, cupped, cymbiform, declining, diminishing, dish-shaped, dished, dishing, dishlike, dwindling, dying, ebbing, fading, funnel-breasted, funnel-chested, funnel-shaped, hollow, hollowed, incurved, incurving, incurvous, infundibular, infundibuliform, navicular, naviform, receding, retiring, saucer-shaped, scaphoid, scyphate, shrinking, sinking, spoonlike, sunk, sunken, waning