Scold concealed in church (5)
I believe the answer is:
chide
'scold' is the definition.
(synonyms)
'concealed in church' is the wordplay.
'concealed' becomes 'hid' ('hide' can be a synonym of 'conceal').
'in' indicates putting letters inside.
'church' becomes 'CE' (Church of England).
'hid' put into 'ce' is 'CHIDE'.
(Other definitions for chide that I've seen before include "Seeing scold" , "Santa's laugh" , "Tear off strip" , "Censure angrily" , "lecture" .)