A mark of the form , placed in Roman inscriptions over consonants to denote
doubling, like the Arabic tashdîd.
The character is of rare
occurrence in existing inscriptions, being most frequently found in those of the early
Augustan period (C. I. L.
v. 1361; x. 3743). It is mentioned by the grammarians
Marius Victorinus (p. 2456) and Isidorus (
Orig. i. 26