Prissy (4)
I believe the answer is:
prim
'prissy' is the definition.
(I know that prissy can be written as prim)
This is the entire clue.
(Other definitions for prim that I've seen before include "Stiffly correct" , "Prudish, formal" , "Proper (type of rose?)" , "Strait-laced - prudish" , "Affectedly formal" .)