WordNet sense 1 (affectedly dainty or refined):

dainty, mincing, niminy-piminy, twee

WordNet sense 2 ((used of persons and their behavior) cultivated and genteel):

refined

WordNet sense 3 (exaggeratedly proper):

priggish, prissy, prudish, puritanical, straitlaced, square-toed, straightlaced, straight-laced, strait-laced, tight-laced, Victorian

WordNet sense 4 (marked by suitability or rightness or appropriateness):

proper

WordNet sense 5 (dress primly):

prim out, prim up