Something said about old German currency (6)
I believe the answer is:
remark
'something said' is the definition.
(a comment or utterance)
'about old german currency' is the wordplay.
'about' becomes 're' (common abbreviation for 'with reference to').
'old german currency' becomes 'Mark' (former currency of Germany).
're'+'mark'='REMARK'
(Other definitions for remark that I've seen before include "Observation - notice" , "Comment, observation" , "Make mention of" , "Written or spoken comment" , "Comment or mention" .)