Comment, on record (6)
I believe the answer is:
remark
'comment' is the definition.
(a remark is a spoken comment)
'on record' is the wordplay.
'on' becomes 're' ('on' can be mean 'with reference to').
'record' becomes 'mark' (marking is a kind of recording).
're'+'mark'='REMARK'
(Other definitions for remark that I've seen before include "Incidental observation" , "what someone says?" , "Comment or mention" , "Something said; take notice of" , "Make mention of" .)