parvenu

\PAR-vuh-noo; -nyoo\, noun:

1. 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.

"Shelley knew that Jake was a parvenu. It was his Dom Perignon Slip n' Slide that gave it away."

adjective: 1. Being a parvenu; also, like or having the characteristics of a parvenu.

"Carrot sticks? How very parvenu."