FERIA, in the Roman Catholic breviary, is applied to the several days of the week; thus Monday is the feria secunda, and Tuesday the feria tertia, though these days are not working days, but holidays. The occasion of this was, that the first Christians were accustomed to keep the Easter week holy, calling Sunday the prima feria, and so on; hence the term feria was given to the days of every week. But besides these, there were extraordinary feriae, as the three last days of Passion-week, the two following Easter-day, and the second feria of Rogation.