Engineering: aerodynamics: camber
An expansion to pao's excellent description, above.
Camber is any upward convex curvature in a structure, especially an aerodynamic shape such as a wing or a sail. A line drawn between the two endpoints of the arc is the chord of the arc. The camber ratio is the maximum depth of the arc divided by the length of the chord.
The camber ratio is an important characteristic of any aerodynamic shape, but by itself it does not describe the arc.
References:- Marino, Emiliano; The Sailmaker's Apprentic: A guide for the self-reliant sailor; International Marine; © 1994 International Marine/Ragged Mountain Press; ISB 0-07-157980-X