Ageing former nurse — the last to use perfume (9)
I believe the answer is:
senescent
'ageing' is the definition.
('senescent' can be a synonym of 'ageing')
'former nurse the last to use perfume' is the wordplay.
'former nurse' becomes 'sen' (I've seen this in other clues).
'the last to' says to take the final letters.
'perfume' becomes 'scent' ('scent' can be a synonym of 'perfume').
The final letter of 'use' is 'e'.
'sen'+'e'+'scent'='SENESCENT'
(Other definitions for senescent that I've seen before include "Ageing" , "Growing old" , "characteristic of old age" , "Showing the deterioration of age" , "Showing signs of age" .)