ancient Roman festival days during which the gods were honoured and all business, especially lawsuits, was suspended. Feriae were of two types: feriae privatae and feriae publicae. The feriae privatae, usually celebrated only by families or individuals, commemorated an event of personal or ancestral importance. Included in this group were the feriae denicales, or 10 days of mourning observed by a family after the death of one of its members.

The holidays observed by all Romans, the feriae publicae, were of three different types: feriae stativae, held annually on a fixed date; feriae conceptivae, movable festivals celebrated annually on days appointed by priests or magistrates; and feriae imperativae, held at official command during extreme emergencies and after great victories.

All feriae publicae were generally observed by prayers, sacrifices, and visits to temples; in addition, the feriae stativae and feriae conceptivae usually included feasts. After the official recognition of Christianity, Christian holidays were substituted for the old system of feriae.