curvature
This term describes a precise geometric property rather than a general shape. It evokes a sense of mathematical measurement and physical tension, focusing on the specific rate of bending at a given point. It is most frequently encountered in technical fields like physics, architecture, and optics. While a curve is the object itself, curvature is the quality of that object. Using this word suggests a professional or scientific perspective, shifting the focus from the visual appearance of a bend to the structural or mathematical reality of the arc.
Countable when referring to different types or specific instances of bending in a design (the curvatures of the fuselage). Uncountable when discussing the general property of being curved in a scientific context (the curvature of spacetime).