America needs to get old in employment (5)
I believe the answer is:
usage
'employment' is the definition.
('usage' can be a synonym of 'employment')
'america needs to get old' is the wordplay.
'america' becomes 'us' (abbreviation for the United States).
'needs' means one lot of letters go next to another.
'to get old' becomes 'age' ('age' can be a synonym of 'get old').
'us'+'age'='USAGE'
'in' acts as a link.
(Other definitions for usage that I've seen before include "Usual practice" , "Customary practice" , "Silly little thing" , "Habit" , "Application" .)