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 or paleographic evidence available from such an early time.