Requiescat in pace is a Latin prayer meaning rest in peace.
An example of requiescat in pace is what would be on someone's tombstone.
requiescat (in pace)
may he or she rest (in peace): a prayer for a dead person: the phrase re·qui·es′cant· (in pace) means “may they rest (in peace)”
Origin of requiescat (in pace)L, subjunctive of requiescere (see re- and quiescent); pace, ablative of pax, peace
- May he/she rest in peace.