Apocrisiarius (Α᾿ποκρισιάριος; Lat. Responsalis), literally a respondent, the title of a legate to negotiate concerning matters ecclesiastical. Justinian (Novell. 6) calls the Apocrisiarii those "who administer the affairs of the churches." At first they were bishops, but afterward priests or deacons were substituted, and the term seems to have been applied to any one acting as locum-tenens for a bishop (or even monastery) in ecclesiastical matters; but the name was principally applied to the pope's nuncio at Constantinople, who resided there to receive the pope's instructions and to report the answers of the emperor. This custom ended with the Iconoclast divisions. After Charlemagne had been crowned emperor, the popes conferred the name and the office of apocrisiarius upon the imperial arch-chaplain. Later the name apocrisiarius became a mere title, which the arch-chaplains of the palace bore, without being any longer representatives of the pope. — Suicer, Thes. p. 456; Collier, Hist. Dict. vol. 3, Suppl; Landon, Eccl. Dict. 1, 446.