"Superman" actor Christopher (5)
I believe the answer is:
reeve
'superman actor christopher' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for reeve that I've seen before include "Pass a rope through a ring" , "Feudal official of medieval England" , "estate supervisor" , "Former official - female ruff" , "Thread (rope) through a ring, old official" .)