Lizard with a dewlap (6)
I believe the answer is:
iguana
'lizard with a dewlap' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for iguana that I've seen before include "Lizard Darwin found in the Galapagos" , "Could be a monitor" , "Tropical American lizard" , "Something like a monitor" , "Large tree-climbing lizard of tropical America" .)