Oriscus

an Oriscus is a type of neume found in gregorian chant.

It is a single neume, meaning it represents one pitch, unlike a compound neume, representing a sequence of more than one pitch.

It is considered an ornamental neume, like the strophicus, quilisma, salicus, and pressus, but the original meaning of the ornament is unclear. It is usually found added to another neume as an auxiliary note. Some modern chant editions replace the sign with a regular punctum.