parvenu (n.)

"upstart," 1802, from French parvenu, "said of an obscure person who has made a great fortune" (Littré); noun use of past participle of parvenir "to arrive" (12c.), from Latin pervenire "to come up, arrive, attain," from per- "through" (from PIE root *per- (1) "forward," hence "through") + venire "to come," from a suffixed form of PIE root *gwa- "to go, come." One newly arisen to notice, especially by an accident of fortune and beyond his birth or apparent deserts, but who is intent to persuade other people that he is entitled to it. As an adjective from 1828.