The Collaborative International Dictionary of English v.0.48:

Proletarian \Prol`e*ta"ri*an\, a. [L. proletarius. See
   Proletary.]
   Of or pertaining to the proletaries; belonging to the
   commonalty; hence, mean; vile; vulgar. "Every citizen, if he
   were not a proletarian animal kept at the public cost." --De
   Quincey. -- n. A proletary.
   [1913 Webster]

WordNet (r) 3.0 (2006):

proletarian
    adj 1: belonging to or characteristic of the proletariat
    n 1: a member of the working class (not necessarily employed);
         "workers of the world--unite!" [syn: proletarian,
         prole, worker]

Moby Thesaurus II by Grady Ward, 1.0:

54 Moby Thesaurus words for "proletarian":
   Cockney, Everyman, John Smith, average man, blue-collar worker,
   bourgeois, breadwinner, casual, casual laborer, common laborer,
   common man, commoner, day laborer, employee, factory worker,
   flunky, free lance, free-lancer, full-time worker, hand,
   industrial worker, jobber, jobholder, laborer, laboring man,
   little fellow, little man, menial, middle-class, migrant, moiler,
   navvy, office temporary, pleb, plebeian, roturier, roustabout,
   salaried worker, self-employed person, servant, stiff, temporary,
   toiler, wage earner, wage slave, wageworker, worker, workgirl,
   workhand, working girl, working-class, workingman, workingwoman,
   workman