I. ˈkänˌkāv, esp Brit sometimes -äŋˌ- noun
( -s )
Etymology: Middle French, from concave, adjective
1.
a. : a hollow within a mass or in a surface
Vulcan … splits the cliff and discloses a concave fashioned by his art — E.K.Chambers
b. : a curved recess : a depression resembling a bowl
c. obsolete : the bore of a gun
2.
a. : the inner face of a bowl-shaped structure
b. : the vault of the sky
3. obsolete : a concave lens or mirror
4. : a set of bars bearing teeth, rasps, or rubber facing curved partly around a rotating threshing cylinder as an aid in shelling grain or seeds in a thresher
II. (ˈ) ̷ ̷| ̷ ̷ adjective
Etymology: Middle French, from Latin concavus, from com- + cavus hollow — more at cave
1. obsolete : having a hollow interior
concave … as a worm-eaten nut — Shakespeare
2.
a. : hollowed or rounded inward like the inside of a bowl
b. : having a shape that is thought of as curving inward — opposed to convex
3. : arched in : curving in — used of the side of a curve or surface on which neighboring normals to the curve or surface converge and on which lies the chord joining two neighboring points of the curve or surface; opposed to convex
• con·cave·ly adverb
• con·cave·ness noun -es
III. verb
( -ed/-ing/-s )
transitive verb
: to make concave
intransitive verb
: to curve concavely
IV. noun
: a concave line or surface