The unglossed headword is a very rare adverbial form of the perfect passive participle of the rare verb pareuri/skw, I discover alongside, I invent. It seems here to be extracted from the phrase given. That phrase occurs more fully in Zenobius 2.60, with (as translated here) the standard opening preposition e)pi/ governing the genitive participle. LSJ s.v. pareurhme/nws describe it as a false reading in Zenobius; note, however, that it also occurs in [Plutarch], On the proverbs of the Alexandrians fr.25, besides twice in the present Suda entry.
Curiously, both Zenobius and [Plutarch] speak of 'the' proverb without ever presenting it. Nevertheless we do know that it somehow concerned Bokchoris (Bakenranef), an Egyptian king and lawgiver of the eighth century BCE = 24th dynasty. (On him see e.g. Diodorus Siculus 1.65.1, 1.79.1-3, 1.94.5; Plutarch, Moralia 529E; Tacitus, Histories 5.3.) In all probability, then, the proverb is the one given at tau 723, which Manetho sets in B.'s reign.