Doctor one to talk interminably (5)
I believe the answer is:
drone
'talk interminably' is the definition.
'drone' can be an answer for 'talk' (droning is a kind of talking). I'm unsure of the 'interminably' bit.
'doctor one' is the wordplay.
'doctor' becomes 'Dr' (abbreviation).
'dr'+'one'='DRONE'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for drone that I've seen before include "He buzzes, but not with energy!" , "Bertie Wooster, say" , "Talk boringly; a parasite" , "Bee, speak tediously" , "small creature" .)