ἐπισυμμαχία
From LSJ
Ἕκτορ νῦν σὺ μὲν ὧδε θέεις ἀκίχητα διώκων → Hector, you run in pursuit of something unattainable | Hector, now art thou hasting thus vainly after what thou mayest not attain | Hector, now you are hasting thus vainly after what you may not attain
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.