Status of a holy man in church (5)
I believe the answer is:
'status' is the definition.
(I know that caste is a type of status)
'a holy man in church' is the wordplay.
'holy man' becomes 'st' (abbreviation for saint).
'in' indicates putting letters inside.
'church' becomes 'CE' (abbreviation for Church of England).
'ast' put into 'ce' is 'CASTE'.
'of' is the link.
(Other definitions for caste that I've seen before include "Level in society" , "Large, long-necked, wading bird" , "Hindu social rank" , "Social class or rank" , "Hereditary social class in Hindu society" .)