Definition of parvenu in English:
 parvenu
noun ˈpɑːvənuːˈpɑːvənjuːˈpɑrvəˌn(j)u
derogatory A person of humble origin who has gained wealth, influence, or celebrity.
 the political inexperience of a parvenu
as modifier cynical parvenu bureaucrats
 Example sentencesExamples
-  You rather liked parvenus: they had energy; they knew what they wanted.
 -  And yet one often hears the bitterness of a displaced generation: ‘How many out of this avalanche of parvenus will stay the course?’
 -  The others are parvenus and upstarts in comparison.
 -  He presented himself as a supremely patrician figure, so different from the vulgar parvenues of the Thatcher cabinet.
 -  It sounds good that some of the parvenus have volunteered to pay taxes.
 
 Synonyms
upstart, social climber, arriviste, vulgarian
the nouveau riche, the new rich
Origin
  
Early 19th century: from French, literally 'arrived', past participle of parvenir, from Latin pervenire 'come to, reach'.
   Definition of parvenu in US English:
 parvenu
nounˈpɑrvəˌn(j)uˈpärvəˌn(y)o͞o
derogatory A person of obscure origin who has gained wealth, influence, or celebrity.
 the political inexperience of a parvenu
as modifier he concealed the details of his parvenu lifestyle
 Example sentencesExamples
-  You rather liked parvenus: they had energy; they knew what they wanted.
 -  He presented himself as a supremely patrician figure, so different from the vulgar parvenues of the Thatcher cabinet.
 -  The others are parvenus and upstarts in comparison.
 -  And yet one often hears the bitterness of a displaced generation: ‘How many out of this avalanche of parvenus will stay the course?’
 -  It sounds good that some of the parvenus have volunteered to pay taxes.
 
 Synonyms
upstart, social climber, arriviste, vulgarian
Origin
  
Early 19th century: from French, literally ‘arrived’, past participle of parvenir, from Latin pervenire ‘come to, reach’.