or SINCCELLUS, an ancient officer in the family of the patriarchs, and other prelates of the eastern church. The word, in the corrupt Greek, εὐγενῆς, signifies a person who lies in the chamber with another; a chamber-fellow, or olum. The syncellus was an ecclesiastic, who lived with the patriarch of Constantinople, to be a witness of his conduct; whence it is, that the syncellus was also called the patriarch's eye, because his business was to observe and watch. The other prelates had also their syncelli, who were clerks living in the house with them, and even lying in the same chamber, to be witnesses of the purity of their manners. Afterwards the office degenerated into a mere dignity; and there were made syncelli of churches.—At last it became a title of honour, and was bestowed by the emperor on the prelates themselves; whom they called pontifical syncelli, and syncelli Auguflales.

SYNCHRONISM denotes the happening of several things at the same time. See Chronology.