Thrill doctor, perhaps, in taxi (10)
I believe the answer is:
exhilarate
'thrill' is the definition.
(I know that thrill can be written as exhilarate)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for exhilarate that I've seen before include "Enliven" , "Make very happy or very animated" , "Thrill" , "Cheer" .)