Source : Webster's Revised Unabridged Dictionary (1913)

Incurvate \In*cur"vate\, a. [L. incurvatus, p. p. of incurvare
   to crook; pref. in- in + curvus bent. See {Curve}, and cf.
   {Incurve}.]
   Curved; bent; crooked. --Derham.

Incurvate \In*cur"vate\, v. t. [imp. & p. p. {Incurvated}; p.
   pr. & vb. n. {Incurvating}.]
   To turn from a straight line or course; to bend; to crook.
   --Cheyne.

Source : WordNet®

incurvate
     adj : bent into or having an inward curve [syn: {incurved}]
     v 1: bend inwards; "The body incurvates a little at the back"
     2: cause to curve inward; "gravity incurvates the rays"