When repeated, a 1997 Jim Carrey comedy (4)
I believe the answer is:
liar
'when repeated a 1997 jim carrey comedy' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for liar that I've seen before include "man of fiction?" , "Pinocchio, at times" , "Untruthful person (Billy in Schlesinger film)" , "not straight [one]" , "Bearer of false witness" .)