Ventilates some melodies (4)
I believe the answer is:
airs
I believe this is a double definition.
'ventilates' is the first definition.
('air' can be a synonym of 'ventilate')
'some melodies' is the second definition.
('air' can be a synonym of 'melody')
(Other definitions for airs that I've seen before include "Strain's" , "Melodies or artificial manners" , "Pretentiousness" , "affectation of superiority" , "Voices" .)