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.

imagine ‘imagine’

English

References: PH Hamm: I.3:1, 46:15. – Plan. Sidoli+Berggren: ?
Translation of:
Greek: νοείσθω / νοέω [PH Heiberg: I.3:1, 74:5]
Arabic: وهم [Plan. Sidoli+Berggren: 14, 280, 441, 486, 498]