Bluenose (5)
I believe the answer is:
prude
'bluenose' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for prude that I've seen before include "Puritan, prig" , "Type overly concerned with decorum" , "Easily shocked person" , "blusher?" , "One is excessively concerned with propriety and decorum" .)