Corrector

A corrector (English plural correctors) is a person who or object that practices , usually by removing or rectifying errors.

The word is originally a Roman title corrector, derived from the Latin verb corrigere, meaning "to make straight, set right, bring into order."

Apart from the general sense of anyone who corrects mistakes, it has been used as, or part of (some commonly shortened again to Corrector), various specific titles and offices, sometimes quite distant from the original meaning.

The office of corrector first appears during the Principate in the reign of Trajan (r. 98–117), for extraordinary officials of senatorial rank, who were tasked with investigating and reforming the administration in the provinces. To this end, they were entrusted with full imperium maius, which extended also to territories normally exempt from the authority of the Emperor's provincial governors: the free cities of the Greek East, the senatorial provinces, as well as Italy herself. The full title of these officials, from their institution to the end of the 3rd century, was in Latin legatus Augusti pro praetore [missus] ad corrigendum [ordinandum] statum, in Greek rendered as πρεσβευτὴς καἰ ἀντιστράτηγος Σεβαστοῦ διορθωτὴς [or ἐπανορθωτὴς] (presbeutes kai antistrategos Sebastou diorthotes/epanorthotes). From the late 3rd century on, the title was increasingly, and afterwards exclusively, simplified as corrector in Latin and διορθωτὴς (or ἐπανορθωτὴς) in Greek.

The sending of correctores to the Greek free cities, as well as to Italy, which as a metropolitan territory formally enjoyed a status different from the provinces, began a process of slow degradation of their distinct legal status and their gradual assimilation to the "ordinary" provinces, a process completed with the reforms of Diocletian (r. 284–305). Thus, at the start of the 4th century, all Italian districts (and Sicily) had a corrector as governor, although by the middle of the century most were replaced by governors with the rank of consularis. In the administrative division as preserved in the Notitia Dignitatum, the correctores held the senatorial rank of vir clarissimus. Those of the West Roman Empire ranked between the consulares and the ordinary praesides, while in the East Roman Empire, they ranked below the praesides.

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