Napier’s power to record a beat for listeners? (9)
I believe the answer is:
logarithm
'napier's power' is the definition.
(John Napier originated logarithms)
'record a beat for listeners?' is the wordplay.
I cannot quite understand how this works, but
'record' could be 'log' (logging is a kind of recording) and 'log' is found within the answer.
'a' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
(Other definitions for logarithm that I've seen before include "Power to which base number must be raised to obtain a given number" , "It undoes power" , "Aid to mathematical calculation" , "Exponent" , "Mathematical aid simplifying multiplication and division - a girl moth (anag)" .)