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.

μεσονύκτιον ‘midnight’

Greek. – Grammar: n.

References: Alm. Heiberg: II.9, 145:7
Translated into:
Arabic: نصف الليل [Alm. MS Tunis: 31b.4]
Arabic: (خطّ) نصف النهار تحت الأرض  [Alm. MS Leiden: f. 24v.38-39]
Modern translations:
English: midnight [Alm. Toomer: 104]