Mackintosh confuses canto with air (8)
I believe the answer is:
raincoat
'mackintosh' is the definition.
(I've seen this before)
'confuses canto with air' is the wordplay.
'confuses' indicates anagramming the letters.
'with' says to put letters next to each other.
'canto' put after 'air' is 'aircanto'.
'aircanto' anagrammed gives 'RAINCOAT'.
(Other definitions for raincoat that I've seen before include "Wet weather wear" , "Water-resistant outer garment" , "Waterproof outer garment" , "protection against the elements" , "clothing" .)