Drafty (4)
I believe the answer is:
airy
'drafty' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for airy that I've seen before include "Jaunty - unsubstantial - offhand" , "Well-ventilated; casual" , "Light and insubstantial" , "Open and spacious" , "Sprightly" .)