This entry (lacking, Adler reports, in ms A) has no equivalent in other lexica.
The headword, presumably extracted from the quotation given, is an adjective in the masculine/feminine accusative singular; see generally LSJ s.v. sunexh/s, and cf. pi 2438 (gloss), and cognates at sigma 1523, sigma 1524, sigma 1526, and sigma 1527.
[1] The gloss is the neuter (nominative, vocative and) accusative singular of the adjective a)kata/paustos; see generally LSJ s.v.
[2] A faulty version of part of Aelian fr. 48 Hercher (Domingo-Forasté 51a, pp. 45-6), recounting abuses which the Ephesian tyrant Pythagoras inflicted upon the daughter of one of his enemies. See already, more fully and correctly (with 'guard' and 'girl' in the singular), at pi 3122. [In her critical apparatus Adler reports that ms F does have a singular guard, while GVM exacerbate the corruption by pluralizing 'constant'.]