parvenu PAR-vuh-noo; -nyoo, noun: One that has recently or suddenly risen to a higher social or economic class but has not gained social acceptance of others in that class; an upstart.

adjective: Being a parvenu; also, like or having the characteristics of a parvenu.

 But the favourite's power and influence provoke intense ill-feeling among other courtiers, who regard him as a sinister usurping parvenu with ideas above his station, or perhaps even a sorcerer. --Francis Wheen, "The whole truth about Peter's friends," The Guardian, January 31, 2001 

 However, the Creoles, French, Spanish, and Acadians who preceded the American parvenus were deeply entrenched and incredibly snobbish and clannish in relation to outsiders. --Laurence Bergreen, Louis Armstrong: An Extravagant Life 

 When John Stewart Parnell went up to Magdalene College, Cambridge in 1865 he found that "the sons of moneyed parvenus from the North of England tried to liken themselves to country gentlemen and succeeded in looking like stable boys." --J. Mordaunt Crook, The Rise of the Nouveaux Riches 

 The Progressives were of the educated middle class, angry at the rule of parvenu financiers and industrialists. --Norman Birnbaum, After Progress