The Collaborative International Dictionary of English v.0.48:

Workingman \Work"ing*man\, n.; pl. Workingmen.
   A laboring man; a man who earns his daily support by manual
   labor.
   [1913 Webster]

WordNet (r) 3.0 (2006):

workingman
    n 1: an employee who performs manual or industrial labor [syn:
         workman, workingman, working man, working person]

Moby Thesaurus II by Grady Ward, 1.0:

41 Moby Thesaurus words for "workingman":
   blue-collar worker, breadwinner, casual, casual laborer,
   common laborer, day laborer, employee, factory worker, flunky,
   free lance, free-lancer, full-time worker, hand, industrial worker,
   jobber, jobholder, laborer, laboring man, menial, migrant, moiler,
   navvy, office temporary, operative, proletarian, roustabout,
   salaried worker, self-employed person, servant, stiff, temporary,
   toiler, wage earner, wage slave, wageworker, worker, workgirl,
   workhand, working girl, workingwoman, workman