συμμετέχω
From LSJ
εἰ ἀποκρυπτόντων τῶν Μήδων τὸν ἥλιον ὑπὸ σκιῇ ἔσοιτο πρὸς αὐτοὺς ἡ μάχη καὶ οὐκ ἐν ἡλίῳ → if the Medes hid the sun, the battle would be to them in the shade and not in the sun
English (LSJ)
A partake of with, take part in with, c. dat. pers. et gen. rei, Βάκχαις συμμετασχήσω χορῶν E.Ba.63; τινὶ τῆς μάχης, τῆς ἀριστείας, Plu.Pyrrh.4, TG4: c. dat. pers., PLond.5.1660.19 (viA.D.): c. gen. rei, δορός E.Supp.648; τοῦ ἔργου X.An.7.8.17 (v.l.); βουλῆς Arist.Pol.1330a21: abs., Pl.Tht.181c: cf. συμμετίσχω.
