Rows in church, so rude (6)
I believe the answer is:
coarse
'rude' is the definition.
(I've seen this before)
'rows in church' is the wordplay.
'rows' becomes 'oars' (I've seen this in other clues).
'in' means one lot of letters goes inside another.
'church' becomes 'ce' (abbreviation for Church of England).
'oars' inserted inside 'ce' is 'COARSE'.
'so' acts as a link.
(Other definitions for coarse that I've seen before include "Rough-hewn" , "lacking in taste" , "Rought or crude" , "Rude, base" , "Large-grained or rough to the touch" .)