Affected, American university grounds (6)
I believe the answer is:
campus
'university grounds' is the definition.
(I've seen this before)
'affected american' is the wordplay.
'affected' becomes 'camp' (I've seen this before).
'american' becomes 'us'.
'camp'+'us'='CAMPUS'
(Other definitions for campus that I've seen before include "university's environs" , "Pre-planned college layout and grounds" , "educational location" , "University grounds, etc" , "student quarters" .)