Webster's Revised Unabridged Dictionary · 1913

Convex

Convex , adjective

[Latin convexus vaulted, arched, convex, concave, from convehere to bring together: compare French convexe. See Vehicle.]

Rising or swelling into a spherical or rounded form; regularly protuberant or bulging; -- said of a spherical surface or curved line when viewed from without, in opposition to concave.
Drops of water naturally form themselves into figures with a convex surface. — Whewell
Collocations (1)
Double convex , convex on both sides; convexo-convex.

Convex , noun

A convex body or surface.
Half heaven's convex glitters with the flame. — Tickell

This word was often pronounced con-vex' by early writers, as by Milton, and occasionally by later poets.