Canary's home (4)
'canary's home' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for cage that I've seen before include "US avant-garde composer, d. 1992" , "Box of bars to confine an animal" , "Enclosure of wire or metal bars" , "Confined enclosure" , "American composer with centenary this year" .)
(Other definitions for birdcage that I've seen before include "Home for a pet" , "Small aviary" , "Where Polly goes" , "arrangement of bars for singer" , "Enclosure for an avian" .)