Saintly gatekeeper's famous rabbit (5)
I believe the answer is:
peter
'rabbit' is the definition.
(I've seen this in another clue)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for peter that I've seen before include "Saint at the Pearly Gates?" , "Boy's name - safe" , "In whist, play" , "emperor" , "and 14 dn Latest actor to play Doctor Who" .)