Source : Webster's Revised Unabridged Dictionary (1913)

Involute \In"vo*lute\, Involuted \In"vo*lu`ted\, a. [L.
   involutus, p. p. of involvere. See {Involve}.]
   1. (Bot.) Rolled inward from the edges; -- said of leaves in
      vernation, or of the petals of flowers in [ae]stivation.
      --Gray.

   2. (Zo["o]l.)
      (a) Turned inward at the margin, as the exterior lip of
          the Cyprea.
      (b) Rolled inward spirally.