What is Aler Sans Jour?

Legal Definition
Or aller sans jour, in practice. A French phrase which means go without day; and is used to signify that the case has been finally dismissed the court, because there is no further day assigned for appearance. Kitch. 146.
-- Bouviers Law Dictionary
Legal Definition
In old practice, a phrase used to indicate the final dismissal of a case from court without continuance. "To go without day."
-- Black's Law Dictionary