Surgeon harbours desire (4)
I believe the answer is:
urge
'desire' is the definition.
(I've seen this before)
'surgeon harbours' is the wordplay.
'harbours' says the answer is hidden in the clue.
'URGE' is hidden within 'surgeon'.
(Other definitions for urge that I've seen before include "Implore" , "Appeal to" , "Egg on, encourage to proceed" , "Longing" , "Press to do something" .)