CLAVI. - A fastening of the Roman tunic, the clavi were two purple stripes running parallel, passing over the shoulders and descending in front and back to the lower hem. Their width varied according to circumstances, for, at least in early times, it was regulated by strict prescriptions.
Very narrow on the tunics of young people, the clavi worn by adults were distinguished into clavus latus (πλατύσχημος), a privilege of the emperor and the senatorial order, and clavus angustus (στενόσχημος), reserved for the equestrian order. As numerous paintings show, in which the clavus adorns indiscriminately the tunic of every kind of person, this distinction of rank, by the 1st century A.D., had lost much of its original rigor, unless such freedom is to be attributed to the artists, who were inclined to use it as an ornamental motif.
The double denomination was also used to indicate both the tunic itself and the person wearing II.
From the 4th century onward, especially in Coptic tunics, the clavi are found adorned and interrupted so that they remain only at the top and bottom of the tunic.