Musical reference work contains nothing about what's on old record (6)
I believe the answer is:
groove
'record' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe you can see a link between them that I don't see?
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for groove that I've seen before include "in which needle was once employed?" , "Get down" , "Long narrow depression - dance and/or play popular music" , "Spiral track followed by a gramophone needle" , "Long thin furrow" .)