Wrongly retired, so had fun (9)
I believe the answer is:
roistered
'had fun' is the definition.
The definition and answer can be both to do with social activities as well as being past participle verbs.
Maybe you can see an association between them that I can't see?
'wrongly retired so' is the wordplay.
'wrongly' indicates anagramming the letters (I've seen this in other clues).
'retired'+'so'='retiredso'
'retiredso' anagrammed gives 'ROISTERED'.
Can you help me to learn more?
(Other definitions for roistered that I've seen before include "celebrated noisily" , "had a merry time" , "celebrated wildly" , "Behaved boisterously" .)