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.

with the same speed / with a uniform motion‘with a uniform speed’

English

References: Alm. Toomer: 45
Translation of:
Greek: ἰσοταχῶς [Alm. Heiberg: I.7, 25:16, 26:16. – PH Heiberg: I.3:2, 74:10; I.8:3, 80:13; I.10:10, 88:14]
Synonyms:
with a uniform speed[PH Hamm: I.3:2, 46:19]
with uniform speed[PH Hamm: I.8:3, 50:10; I.10:10, 54:11]