Note conclusion to curve (4)
I believe the answer is:
bend
'to curve' is the definition.
(synonyms)
'note conclusion' is the wordplay.
'note' becomes 'b' (musical note).
'conclusion' becomes 'end' (something's conclusion is its end).
'b'+'end'='BEND'
(Other definitions for bend that I've seen before include "Turn, flex" , "submit" , "Crouch" , "Repair" , "Influence, bow" .)