Hector, for one (6)
I believe the answer is:
trojan
'hector for one' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for trojan that I've seen before include "Paris, for example - harmful computer program" , "To work like one is to work hard" , "Dedicated worker" , "Paris, say" , "Traditional type of horse" .)