concave
UK[ˈkɒnkeɪv]US[ˈkɑːnkeɪv]
adj
having an outline or surface that curves inward like the interior of a circle or sphere.
Morpheme Breakdown
con
cave
con
together
cave
hollow
Etymology
the word concave is a direct borrowing from the latin adjective 'concavus', meaning 'arched' or 'vaulted'. it is formed from the prefix 'con-', an intensifier meaning 'thoroughly', and the root 'cavus', meaning 'hollow'. the literal sense of 'thoroughly hollow' described a surface that is deeply curved inward. this concrete, physical meaning has been preserved directly into modern english, where it specifically denotes a surface that curves inward, forming a recess, in contrast to its antonym 'convex'.
Analysis
Structure: con + cave
con- (latin origin, a variant of 'com-', meaning 'together' or 'with'); cave (latin origin, from 'cavus', meaning 'hollow')
Examples
the inside surface of a spoon is concave.
the architect designed a roof with a concave curve to channel rainwater.
the lens is concave on one side and convex on the other.