Gecko or iguana (6)
I believe the answer is:
lizard
'gecko or iguana' is the definition.
(I know that gecko is a type of lizard)
This is the entire clue.
(Other definitions for lizard that I've seen before include "Reptile with two pairs of legs" , "Gecko, for example" , "Kind of reptile - chameleon is one" , "leading to a windswept village" , "part of Cornish coast" .)