LSJ
εως, ἡ, coordinate or parallel existence, Porph. Sent. 44 (pl.), Procl. in R. 1.38 K., al. ; by-product, ἐκτροπὴ καὶ π. ἐστι τοῦ κατὰ φύσιν τὸ παρὰ φύσιν Simp. in Cael. 429.34, cf. in Ph. 1262.8.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
ἡ, Neben-, zufällige Existenz, Sp.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)