Definition from Wiktionary, the free dictionary
From Latin convexus (“arched”).
- (RP) IPA: /ˈkɒnvɛks/, X-SAMPA: /"kQnvEks/
- (GenAm) IPA: /ˈkɑnvɛks/, X-SAMPA: /"kAnvEks/
- The noun was often stressed on the second syllable by early writers, such as Milton, and occasionally by later poets.
- curved or bowed outward like the outside of a bowl or sphere or circle
- Drops of water naturally form themselves into figures with a convex surface.
- (mathematics, not comparable) (Of a set of points) such that for any two points in the set, every point between those two points is also in the set
- (analysis, not comparable) (of a real-valued function on the reals) such that the value at any point, is no larger than the interpolated value thereat, based on the values at any two points between which the first point is contained
Derived terms 
curved or bowed outward like the outside of a bowl or sphere or circle
convex (plural convexes)
- Oxford English Dictionary, Second Edition, 1989