Said to be correct ceremony (4)
I believe the answer is:
rite
'ceremony' is the definition.
(I know that rite is a type of religious ceremony)
'said to be correct' is the wordplay.
'said to be' indicates a 'sounds like' (homophone) clue.
'correct' becomes 'right' (right can mean correct).
'right' sounds like 'RITE'.
(Other definitions for rite that I've seen before include "Ceremonial act" , "Uncomplaining person" , "something like mass" , "Formal procedure" , "Custom" .)