1.  flexure(n = noun.state) flection, flexion - the state of being flexed (as of a joint);
Derived form verb flex₄

2.  flexure(n = noun.shape) bend, crease, crimp, fold, plication - an angular or rounded shape made by folding; "a bend of his elbow"; "a crease in his trousers"; "a flexure of the colon"; "a fold in the napkin"; "a plication on her blouse"
Derived form verb flex₃

3.  flexure(n = noun.act) flexion - act of bending a joint; especially a joint between the bones of a limb so that the angle between them is decreased;
Derived form verb flex₃, verb flex₄

1.  The act of flexing or bending; a turning or curving; flexion; hence, obsequious bowing or bending. [1913 Webster]

2.  A turn; a bend; a fold; a curve. [1913 Webster]

3.  The last joint, or bend, of the wing of a bird. [1913 Webster]

4.  The small distortion of an astronomical instrument caused by the weight of its parts; the amount to be added or substracted from the observed readings of the instrument to correct them for this distortion. [1913 Webster]

flexure, n.
1 a the act of bending or the condition of being bent. b a bend, curve, or turn.
2 Math. the curving of a line, surface, or solid, esp. from a straight line, plane, etc.
3 Geol. the bending of strata under pressure.

Derivative:
flexural adj.

Etymology:
L flexura (as FLEX(1))

N  curvature, curvity, curvation, incurvature, incurvity, incurvation, bend, flexure, flexion, flection, conflexure, crook, hook, bought, bending, deflection, deflexion, inflection, inflexion, concameration, arcuation, devexity, turn, deviation, detour, sweep, curl, curling, bough, recurvity, recurvation, sinuosity, kink, carve, arc, arch, arcade, vault, bow, crescent, half-moon, lunule, horseshoe, loop, crane neck, parabola, hyperbola, helix, spiral, catenary, festoon, conchoid, cardioid, caustic, tracery, arched ceiling, arched roof, bay window, bow window, sine curve, spline, spline curve, spline function, obliquity, curved, curviform, curvilineal, curvilinear, devex, devious, recurved, recurvous, crump, bowed, vaulted, hooked, falciform, falcated, semicircular, crescentic, sinusoid, parabolic, paraboloid, luniform, lunular, semilunar, conchoidal, helical, double helical, spiral, kinky, cordiform, cordated, cardioid, heart shaped, bell shaped, boat shaped, crescent shaped, lens shaped, moon shaped, oar shaped, shield shaped, sickle shaped, tongue shaped, pear shaped, fig shaped, kidney-shaped, reniform, lentiform, lenticular, bow-legged, oblique, circular, aduncated, arclike, arcuate, arched, beaked, bicorn, bicornuous, bicornute, clypeate, clypeiform, cymbiform, embowed, galeiform, hamate, hamiform, hamous, hooked, linguiform, lingulate, lobiform, lunate, navicular, peltate, remiform, rhamphoid, rostrate, rostriferous, rostroid, scutate, scaphoid, uncate, unguiculate, unguiform.

N  fold, plicature, plait, pleat, ply, crease, tuck, gather, flexion, flexure, joint, elbow, double, doubling, duplicature, gather, wrinkle, rimple, crinkle, crankle, crumple, rumple, rivel, ruck, ruffle, dog's ear, corrugation, frounce, flounce, lapel, pucker, crow's feet, plication, folded, fluted, pleated.