The Collaborative International Dictionary of English v.0.48:

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.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

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.
   [1913 Webster]

WordNet (r) 3.0 (2006):

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