Source : Webster's Revised Unabridged Dictionary (1913)

Genu \Ge"nu\, n.; pl. {Genua}. [L., the knee.] (Anat.)
   (a) The knee.
   (b) The kneelike bend, in the anterior part of the callosum
       of the brain.

Source : WordNet®

genu
     n : hinge joint in the human leg connecting the tibia and fibula
         with the femur and protected in front by the patella
         [syn: {knee}, {knee joint}, {articulatio genus}]
     [also: {genua} (pl)]