CHAPEL, a place of religious worship,  a name properly applied to that of a Christian religious body, but sometimes to any small temple of pagan worship (Lat. sacellum). The word is derived through the O. Fr. chapele, modern chapelle, from the Late Lat. capelle or cappella, diminutive of cappa, a cape, particularly that of a monk. This word was transferred to any sanctuary containing relics, in the early history of the Frankish Church, because the cloak of St Martin, cappa brevior Sancti Martini, one of the most sacred relics of the Frankish kings, was carried in a sanctuary or shrine wherever the king went; and oaths were taken on it (see Ducange, Glossarium, s.v. Capella). Such a sanctuary was served by a priest, who was hence called capellanus, from which is derived the English "chaplain" (q.v.). The strict application of the word to a sanctuary containing relics was extended to embrace any place of worship other than a church, and it was synonymous, therefore, with "oratory" (oratorium), especially one attached to a palace or to a private dwelling-house. The celebrated Sainte Chapelle in Paris, attached to what is now the Palais de Justice, well illustrates the early and proper meaning of the word. It was built (consecration, 1248) by St Louis of France to contain the relic of the Crown of Thorns, ransomed by the king from the Venetians, who held it in pawn from the Latin emperor of the East, John of Brienne, lately dead. The chapel served as the sanctuary of the relic lodged in the upper chapel, and the whole building was attached as the place of worship to the king's palace. This, the primary meaning, survives in the chapels usually placed in the aisles of cathedrals and large churches. They were originally built either to contain relics of a particular saint to whom they were dedicated, or the tomb of a particular family.
In the Church of England the word is applied to a private place of worship, attached either to the palaces of the sovereign, "chapels royal," or to the residence of a private person, to a college, school, prison, workhouse, etc. Further, the word has particular legal applications, though in each case the building might be and often is styled a church. These are places of worship supplementary to a parish church, and may be either "chapels of ease," to ease or relieve the mother-church and serve those parishioners who may live far away, "parochial chapels," the "churches" of ancient divisions of a very large and widely scattered parish, or "district chapels," those of a district of a parish divided under the various church building acts. A "free chapel" is one founded by the king and by his authority, and visited by him and not by the bishop. A "proprietary chapel" is one that belongs to a private person. They are anomalies to the English ecclesiastical law, have no parish rights, and can be converted to other than religious purposes, but a clergyman may be licensed to perform duty in such a place of worship. In the early and middle part of the 19th century such proprietary chapels were common, but they have practically ceased to exist. "Chapel" was early and still is in England the general name of places of worship other than those of the established Church, but the application of "church" to all places of worship without distinction of sect is becoming more and more common. The word "chapel" was in this restricted sense first applied to places of worship belonging to the Roman Church in England, and was thus restricted to those attached to foreign embassies, or to those of the consorts of Charles I. and II. and James II., who were members of that church. The word is still frequently the general term for Roman Catholic churches in Great Britain and always so in Ireland. The use of "chapel" as a common term for all Nonconformist places of worship was general through most of the 19th century, so that "church and chapel" was the usual phrase to mark the distinction between members of the established Church and those of Nonconformist bodies. Here the widened use of "church" noticed above has been especially marked. Most of the recent buildings for worship erected by Nonconformist bodies will be found to be styled Wesleyan, Congregational, etc., churches. It would appear that while the word "chapel" was not infrequent in the early history of Nonconformity, "meeting-house" was the more usual term.
From the architectural point of view the addition of chapels to a cathedral or large church assumes some historical importance in consequence of the changes it involved in the plan. It was the introduction of the apsidal chapels in the churches of France which eventually led to the chevet or cluster of eastern chapels in many of the great cathedrals, and also sometimes to the extension of the transept so as to include additional apsidal chapels on the east side. In France, and to a certain extent in Italy, the multiplication of chapels led to their being placed on the north and south side of the aisles, and in some cases, as at Albi in France, to the suppression of the aisles and the instalment of the chapels in their place. The chapels of the colleges at Oxford and Cambridge are sometimes of large dimensions and architecturally of great importance, that of Christ Church being actually the cathedral of Oxford; among others may be mentioned the chapel of Merton College, and the new chapel of Exeter College, both in Oxford, and the chapel of King's College, Cambridge, which is roofed over with perhaps the finest fan-vault in England. (See Vault, Plate II., fig. 19.)
 The only other English sense is that of a printer's workshop, or the body of compositors in it, who are presided over by a "father of the chapel."
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)