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

محيط الدائرة‘circumference’

Arabic

References: Alm. MS Tunis:
Translation of:
Greek: περίμετρος [Alm. Heiberg: I.10, 31:11]
Synonyms:
الخطّ المحيط[PH Morelon: I.3:1, 19:5]
الخطّ المحيط[Plan. Sidoli+Berggren: 453, 455, 458]
الدائرة[Alm. MS Leiden: f. 6r]
خطوط محيطة بالدوائر[PH Morelon: I.19, 75:17]
دور[PH Morelon: I.18, 71:15]
محيط[Alm. MS Tunis: ]