Disparaging remark made by a son being taken round island (9)
I believe the answer is:
aspersion
'disparaging remark' is the definition.
(I've seen this before)
'a son being taken round island' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'being' becomes 'person' (person is a kind of being).
'taken round' indicates putting letters inside.
'island' becomes 'i' (geographical abbreviation).
'person' placed around 'i' is 'persion'.
'a'+'s'+'persion'='ASPERSION'
'made by' acts as a link.
(Other definitions for aspersion that I've seen before include "reflection" , "Cast this slur" , "Malicious remark" , "Negative comment" , "Slander" .)