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.

ad infimum inferius descendere ‘getting lower’

Latin

References: Alm. Gerard: I.3:30, f. 2rb:10
Translation of:
Arabic: هبط إلى أخفض [Alm. MS Leiden: I.3:30, f. 3v:2-3. – Alm. MS Tunis: I.3:30, f. 2v:20]