D defs.my
Entry 2 senses Webster, 1913

Curvature

/(k?r"v?-t?r; 135)/ · Cur·va·ture · IPA /ˈkɜɹ.və.tʃəɹ/
01 n. The act of curving, or the state of being bent or curved; a curving or bending, normal or abnormal, as of a line or surface from a rectilin…
  1. 1.
    The act of curving, or the state of being bent or curved; a curving or bending, normal or abnormal, as of a line or surface from a rectilinear direction; a bend; a curve.
    “The elegant curvature of their fronds.” Darwin.
  2. 2.
    The amount of degree of bending of a mathematical curve, or the tendency at any point to depart from a tangent drawn to the curve at that point.(Math.)
Phrases & compounds
Aberrancy of curvature — the deviation of a curve from a circular form.
Absolute curvature — See under Absolute.
Angle of curvature — one that expresses the amount of curvature of a curve.
Chord of curvature — See under Chord.
Circle of curvature — See Osculating circle of a curve, under Circle.
Curvature of the spine — an abnormal curving of the spine, especially in a lateral direction.
Radius of curvature — the radius of the circle of curvature, or osculatory circle, at any point of a curve.