Akademik

concave
1. adjective
curved like the inner surface of a sphere or bowl
Ant: convex
2. noun
a) A concave surface or curve.

Aristotle makes [Fire] to move to the concave of the Moon. - Thomas Salusbury (1661).

b) The vault of the sky.
3. verb
To render concave, or increase the degree of concavity.

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