Disparagement is belittlement. When Prince William married Catherine Middleton, there was some disparagement by the public of her non-royal background. Snobs.
Disparagement comes from the Old French desparagier, meaning "marry someone of unequal rank." Disparagement is the act of speaking about someone in a negative or belittling way, and doesn't have to be related to weddings. If someone wins an election because of sneaky, dishonest ads, you can be sure that there will be plenty of disparagement of that candidate in the back rooms of the defeated politician.