Specimen supplied by son, more than enough (6)
I believe the answer is:
sample
'specimen' is the definition.
(thesaurus)
'son more than enough' is the wordplay.
'son' becomes 's'.
'more than enough' becomes 'ample' (I've seen this before).
's'+'ample'='SAMPLE'
'supplied by' is the link.
(Other definitions for sample that I've seen before include "Test piece" , "Small part representative of the whole" , "Specimen, try out" , "Taste; specimen" , "A specimen of maples" .)