CHAPTER-HOUSE (Lat. capitolium, Ital. capitolo, Fr. chapitre, Ger. Kapitelhaus), the chamber in which the chapter or heads of the monastic bodies (see Abbey and Cathedral) assembled to transact business. They are of various forms; some are oblong apartments, as Canterbury, Exeter, Chester, Gloucester, &c.; some octagonal, as Salisbury, Westminster, Wells, Lincoln, York, &c. That at Lincoln has ten sides, and that at Worcester is circular; most are vaulted internally and polygonal externally, and some, as Salisbury, Wells, Lincoln, Worcester, &c., depend on a single slight vaulting shaft for the support of the massive vaulting. They are often provided with a vestibule, as at Westminster, Lincoln, Salisbury and are almost exclusively English.