The Collaborative International Dictionary of English v.0.48:

Iguanidae \Iguanidae\ n.
   A natural family of New World lizards including the common
   Iguana, Iguana iguana.

   Syn: family Iguanidae.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Iguana iguana
    n 1: large herbivorous tropical American arboreal lizards with a
         spiny crest along the back; used as human food in Central
         America and South America [syn: common iguana, iguana,
         Iguana iguana]