Im asking for proof that it was used as an umbrella term for Serbs   Since beside Vlah it says Words and phrases are pejorative if they imply contempt or disapproval The adjective pejorative is synonymous with derogatory derisive dyslogistic and contemptuous When used as an adjective pejorative has two meanings  tending to make or become worse and  tending to disparage or belittle When used as a noun pejorative means a belittling or disparaging word or expression   THUS Im asking for you to prove your claims that it was an umbrella term