1. (a.) Hollow and curved or rounded inward; in opposition to convex; as, a concave mirror; the concave arch of the sky\.

2. (a.) Hollow; void of contents.

3. (n.) A hollow; an arched vault; a cavity; a recess.

4. (n.) A curved sheath or breasting for a revolving cylinder or roll.

5. (v. t.) To make hollow or concave.

arched arciform arclike arcual bandy boat-shaped boatlike bowed bowl-shaped bowlike bowllike cavelike cavernous concaved convex craterlike cup-shaped cupped cymbiform dish-shaped dished dishing dishlike embowed funnel-breasted funnel-chested funnel-shaped gibbose gibbous hollow hollowed humpbacked humped humpy hunched hunchy incurved incurving incurvous infundibular infundibuliform navicular naviform oxbow retiring retreating saucer-shaped scaphoid scyphate spoonlike sunk sunken vaulted