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.

emissores radiorum ‘aphetical planets casting rays’

Latin. – Grammar: noun.

References: Pontano: LXXIIIc. 8
Translation of:
Greek: ἀφέτης [Pontano: p. 328]