The Collaborative International Dictionary of English v.0.48:

Limpkin \Limp"kin\ (l[i^]mp"k[i^]n), n. (Zool.)
   Either one of two species of wading birds of the genus
   Aramus, intermediate between the cranes and rails. The
   limpkins are remarkable for the great length of the toes. One
   species (Aramus giganteus) inhabits Florida and the West
   Indies; the other (Aramus scolopaceus) is found in South
   America. Called also courlan, and crying bird.
   [1913 Webster]

WordNet (r) 3.0 (2006):

limpkin
    n 1: wading bird of Florida, Cuba and Jamaica having a drooping
         bill and a distinctive wailing call [syn: limpkin,
         Aramus pictus]