Copies of Ὁ Καρπός, a Greek collection of astrological aphorisms that was for centuries attributed to Ptolemy, often contain a variety of common and sometimes not so common abbreviations and symbols for astrological terms. Aphorism 97 in this particular manuscript (BnF gr. 2509) includes three typical abbreviations.
Ὁ κύριοσ τῆσ πανσελήνου ἢ τῆσ συνόδου, ὅτε ἐστὶν ἐπίκεντροϲ, προστελειοῖ τὸ πρᾶγμα, οὗ ἐστιν ἡ ἐρώτησιϲ. [When the ruler of the full moon or of the new moon is angular, the matter about which there is an interrogation is accomplished.]
When I came across these abbreviation in this copy, after seeing them dozens of times, they seem perfectly clear to me. I can readily remember, however, how just a couple years ago, sitting there in the manuscript reading room at the ÖNB and trying to make sense of them, I was happy to have another copy of the text at hand to help figure out what they meant.