 Sicilicus

A sicilicus was an old Latin diacritical mark,  ͗, like a reversed C (Ɔ) placed above a letter and evidently deriving its name from its shape like a little sickle (which is "sicilis" in Latin).The ancient sources say that during the time of the Republic it was placed above a geminate consonant to indicate that the consonant counted twice, although there is hardly any epigraphic and paleographic evidence available from such an early time.