Puritan holding shit stick out (8)
I believe the answer is:
protrude
'stick out' is the definition.
('protrude' can be a synonym of 'stick out')
'puritan holding shit' is the wordplay.
'puritan' becomes 'prude' ('prude' can be a synonym of 'puritan').
'holding' is an insertion indicator.
'shit' becomes 'rot' ('rot' can be a synonym of 'shit').
'prude' placed around 'rot' is 'PROTRUDE'.
(Other definitions for protrude that I've seen before include "Bulge" , "Stand out" , "Stick outwards" , "Come out" , "Stick out, project from a surface" .)