Presidential candidate loses weight with microchip surgery (6)
I believe the answer is:
clinic
'surgery' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for clinic that I've seen before include "Health centre" , "Place for specialised treatment or advice" , "Place or session at which treatment or advice is given" , "Doctor's session" , "medical department" .)