Dalmatica, a sacerdotal vestment in the Roman Catholic church, distinctive at present of deacons and subdeacons. Originally it was borrowed by the Romans from the Dalmatians, and appears to have been an ample flowing vestment descending to the heels, with wide sleeves which reached to the elbows. It was at first, as a garment of barbarian origin, looked upon with disfavor; and when Commodus and Heliogabalus appeared with it in public, the people manifested their displeasure. In the 2d century, however, it came into favor, and was worn by bishops, priests, and deacons. St. Cyprian was clothed in a dalmatica when he set out for the place of his execution. At a very early period it was worn by the popes in public functions. John the Deacon mentions the dalmatica of Gregory the Great. Subsequently it became the appropriate vestment of deacons and subdeacons when assisting the priest at the altar. Popes and bishops when they celebrate pontifical mass still wear the silken dalmatica over the alb and beneath the chasuble. Its color originally was white; but it soon came to be adorned with two purple bands extending from the shoulders the whole length downward before and behind.
As worn at present, it is open at the sides, with a hole in the middle for the head; and of the wide sleeves only the upper part covering the arms to the elbows remains. The French make it of very stiff cloth; but the Catholics of other countries make it of more graceful shape, and of silk like the chasuble.