fe·ria /ˈfɪriə, ˈfɛr-/
  Fe·ri·a n.; pl. Feriæ  Eccl. A week day, esp. a day which is neither a festival nor a fast.
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  feria
       n 1: a weekday on which no festival or holiday is celebrated; "in
            the middle ages feria was used with a prefixed ordinal
            number to designate the day of the week, so `secunda
            feria' meant Monday, but Sunday and Saturday were always
            called by their names, Dominicus and Sabbatum, and so
            feria came to mean an ordinary weekday"
       2: (in Spanish speaking regions) a local festival or fair,
          usually in honor of some patron saint
       [also: feriae (pl)]