An archpriest is a non-monastic priest elevated with an honorific rank, equivalent to the monastic archimandrite, though ranking one position lower. Archpriests are styled Very Reverend.
The honor a higher rank is usually given as a recoginition of exemplary service or faithfulness to one's duties while in their current office.
The term protopresbyter (or protopriest) is equivalent to archpriest in Greek practice, while in Slavic usage, a protopresbyter is a rank separate from and higher than archpriest. There are usuaully only a handful of protopresbyters in a given Slavic national church at any one time.
In Greek practice, archpriests wear a pectoral cross to designate their rank, while in Slavic practice, all priests wear pectoral crosses regardless of rank.