Fairy's manner (3)
I believe the answer is:
air
I believe this clue is a double definition.
'fairy's' is the first definition.
(thesaurus)
'manner' is the second definition.
(air is a kind of manner)
(Other definitions for air that I've seen before include "Cause of inflation" , "character" , "what emerges from singer's lungs?" , "Simple melody's" , "Of which 78% is nitrogen" .)