Stimulating device for a front runner (9)
I believe the answer is:
pacemaker
'stimulating device' is the definition.
'pacemaker' can be an answer for 'device' (pacemaker is a kind of device). I'm unsure of the 'stimulating' bit.
'a front runner' is the wordplay.
I cannot really understand how this works, but
'a' is present in the answer.
'runner' could be 'r' (abbreviation) and 'r' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
'for' is the link.
Can you help me to learn more?
(Other definitions for pacemaker that I've seen before include "Device inserted into chest to stimulate heart" , "Cardiac device" , "Heart patient's aid" , "the first in race" , "Implanted device to control the heartbeat" .)