The Collaborative International Dictionary of English v.0.48:

Lameness \Lame"ness\, n.
   The condition or quality of being lame; as, the lameness of
   an excuse or an argument.
   [1913 Webster]

WordNet (r) 3.0 (2006):

lameness
    n 1: disability of walking due to crippling of the legs or feet
         [syn: lameness, limping, gimp, gimpiness,
         gameness, claudication]
    2: an imperfection or defectiveness; "a stylist noted for the
       lameness of his plots"