TRANSEPT (from Lat. trans, across, and septum, enclosure; synonymous terms in other languages are Fr. croisee, nef transvers&e; Ital. crociala; Ger. Querbau, Querschiff), in architecture, the term given to the large and lofty structure which lies at right angles to the nave and aisles of a church. The first example is that which existed in the old St Peter's at Rome, but as a rule it is not found in the early basilicas. At the present day the transept might be better defined as that portion of a cruciform church which extends from north to south across the main body of the building and usually separates the choir from the nave; but to this there are some exceptions, as in Westminster Abbey, where the choir, with its rood screen, occupies the first four bays of the nave; in Norwich two bays; in Gloucester one bay; and Winchester one bay. In some of the English cathedrals there is an eastern transept, as in Canterbury, Lincoln, Salisbury and Worcester; at Durham that which might be regarded as an eastern transept is the chapel of the Nine Altars, and the same is found in Fountains Abbey. Four of the English cathedrals have aisles on east and west sides, viz. Ely, Wells, Winchester and York, while at Chester there are aisles to the south transept only, and at Lincoln, Peterborough and Salisbury on the east side only. In some cases the transept extends to the outer walls of the aisles on'.y, but there are many instances in which it is carried beyond, as at Lincoln (225 ft. long), Ely (180 ft.), Peterborough (iSoft.), Durham (175 ft.) and Norwich (172 ft.); in all these cases the transept is carried three bays beyond; in York (220 ft.), St Albans (170 ft.), Lichfield (145 ft.) and Canterbury, east transept (165 ft.), two bays beyond; and in Canterbury, western transept (130 ft.), Chichester (160 ft.) and Worcester (130 ft.), only one bay on each side, the dimension in all cases being taken within the north and south walls of the transept.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)