The Collaborative International Dictionary of English v.0.48:

Workyday \Work"y*day`\, n. [See Workday, Workingday.]
   A week day or working day, as distinguished from Sunday or a
   holiday. Also used adjectively. [Written also workiday, and
   workaday.] [Obs. or Colloq.]
   [1913 Webster]

         Prithee, tell her but a workyday fortune. --Shak.
   [1913 Webster]