Carrier bringing note back (3)
I believe the answer is:
hod
'carrier' is the definition.
(I've seen this before)
'note back' is the wordplay.
'note' becomes 'doh' (alternative spelling of 'do' as in do re mi).
'back' shows that the letters should be reversed in order.
'doh' back-to-front is 'HOD'.
'bringing' acts as a link.
(Other definitions for hod that I've seen before include "A bricklayer's carrying pole" , "Coal-scuttle" , "Brick-layer's tool" , "Brickie's carrier" , "Coal scuttle" .)