ἐπισυμμαχία
From LSJ
εἰ γάρ κεν καὶ σμικρὸν ἐπὶ σμικρῷ καταθεῖο καὶ θαμὰ τοῦτ᾽ ἔρδοις, τάχα κεν μέγα καὶ τὸ γένοιτο → for if you add only a little to a little and do this often, soon that little will become great (Hesiod W&D, 361-362)
English (LSJ)
ἡ,
A alliance against a common enemy, Philipp. ap. D.12.7 codd. (leg.ἐπιμαχία).
German (Pape)
[Seite 986] ἡ, ein Schutz- u. Trutzbündniß gegen einen gemeinsamen Feind, Dem. 12, 7 (epist. Phil.); Xen. Cyr. 3, 2, 23, v. l.