The Collaborative International Dictionary of English v.0.48:

Proletariat \Prol`e*ta"ri*at\, n. [F.]
   The indigent class in the State; the body of proletarians.
   [1913 Webster]

WordNet (r) 3.0 (2006):

proletariat
    n 1: a social class comprising those who do manual labor or work
         for wages; "there is a shortage of skilled labor in this
         field" [syn: labor, labour, working class,
         proletariat]