The Collaborative International Dictionary of English v.0.48:

Margay \Mar"gay\, margay cat \margay cat\, n. (Zool.)
   A small American wild cat (Felis wiedi syn. Felis
   tigrina), ranging from Mexico to Brazil. It is spotted with
   black. Called also long-tailed cat.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Felis wiedi
    n 1: small spotted wildcat found from Texas to Brazil [syn:
         margay, margay cat, Felis wiedi]