[F., ‘said of an obscure person who has made a great fortune’ (Littré), sbst. use of pa. pple. of parvenir to arrive (at a destination), to rise to a position, make a fortune:L. pervenre to arrive, attain.] 

A. n. A person of obscure origin who has attained wealth or position beyond that of his class; esp. such a one when unfitted for his position, or when making large assumptions for himself on account of his wealth; an upstart. Also transf.
 
   1802 W. GIFFORD tr. Juvenal v. 228 note, His patronage,..like that of many other parvenus, was so burdensome, that the poet, in a fit of spleen, threatens to shake it off entirely. 1826 DISRAELI Viv. Grey II. xiv. ‘Ah! there is nothing like old families!’ remarked Mrs. Million, with all the awkward feelings of a parvenue. 1834 L. RITCHIE Wand. by Seine 68 The Bonaparte people were parvenus, and clung to all the prestiges of the preceding dynasty. 1848 THACKERAY Van. Fair xxxvi, The ladies their wives, who could not bear the parvenue [Rebecca]. 1891 M. O'RELL Frenchm. in Amer. 209 The parvenu is a person who makes strenuous efforts to persuade other people that he is entitled to the position he occupies. 1944 PARTRIDGE Here, There & Everywhere (1950) 54 A word begins its career as a parvenu. 1955 Times 20 Aug. 7/7 To such a man the Jews are not only aggressors and common thieves but parvenus too. 1978 P. VAN GREENAWAY Man called Scavener vii. 95 Genealogy..attracts a growing body of parvenus.
 
B. adj. That has but recently risen to wealth or position; like or characteristic of a parvenu in manners, vulgar display, etc.
 
   1828 J. S. MILL in Westm. Rev. IX. 290 No one licked the dust before the parvenu emperor with greater gusto than the abbé Maury. 1839 POE W. Wilson Wks. 1874 I. 347 A young parvenu nobleman. 1879 Q. Rev. July 14 Other monarchs had treated the parvenu ruler of France with distant arrogance. 1897 Harper's Mag. Apr. 746 There was nothing parvenu in the penniless lad. 1958 Times 12 Nov. 3/5 She sounds a parvenu proletarian, if such a fancy be comprehended. 1978 Amer. N. & Q. XVII. 31/2 Some of the parvenu universities are rapidly approaching maturity.
 

     Hence parvenudom , the domain of parvenus; parvenuism , the habits or practices of parvenus, parvenu character.
 
   1854 LOWELL Jrnl. Italy Prose Wks. 1890 I. 205 A Roman column standing near..satirizes silently their tawdry parvenuism. 1868 W. R. GREG Lit. & Soc. Judgm. 280 [A] piece of inflated affectation in the richest style of parvenuism. 1891 Star 12 Dec. 4/3 The servile grovelling of parvenudom. 1900 Westm. Gaz. 31 Jan. 3/2 How far it is true as a study of Berlin parvenudom, few..could say.