Rob had no right to get the only perfume becoming dated (11)
I believe the answer is:
obsolescent
'dated' is the definition.
Both the answer and definition are adjectives. Perhaps you can see an association between them that I don't see?
'rob had no right to get the only perfume' is the wordplay.
'had no' indicates named letters should be taken away.
'right' becomes 'r' (common abbreviation).
'to get' is a charade indicator (letters next to each other).
'the only' becomes 'sole' (I've seen this before).
'perfume' becomes 'scent' (synonyms).
'rob' with 'r' taken away is 'ob'.
'ob'+'sole'+'scent'='OBSOLESCENT'
'becoming' is the link.
Can you help me to learn more?
(Other definitions for obsolescent that I've seen before include "fading" , "Outdated" , "Getting dated" , "Becoming out of date" , "about to disappear?" .)