PAL

Ptolemaeus Arabus et Latinus

_ (the underscore) is the placeholder for exactly one character.
% (the percent sign) is the placeholder for no, one or more than one character.
%% (two percent signs) is the placeholder for no, one or more than one character, but not for blank space (so that a search ends at word boundaries).

At the beginning and at the end, these placeholders are superfluous.

περὶ τὸ αὐτὸ κέντρον‘concentric’

Greek

References: PH Heiberg: I.3:3, 74:13; I.11:7, 92:12-13
Translated into:
Arabic: مخطوط على مركزه [PH Morelon: I.3:3, 19:10]
Arabic: مركزه مركزه [PH Morelon: I.11:7, 39:19]
Modern translations:
English: with the same center [PH Hamm: I.3:3, 46:21]
English: around the same center [PH Hamm: I.11:7, 56:22]
Synonyms:
ὁμόκεντρος[PH Heiberg: I.3:2, 74:9]