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.

little circle ‘small circle’

English. – Grammar: n.

References: PH Hamm: I.9:6, 52:7; I.10:7, 54:5; I.11:5, 56:12
Translation of:
Greek: κυκλίσκος [PH Heiberg: I.9:6, 84:5; I.10:7, 86:27; I.11:5, 92:1]