βαδιστέον
From LSJ
γραμματική ἐστιν ἐμπειρία τῶν παρὰ ποιηταῖς τε καὶ συγγραφεῦσιν ὡς ἐπὶ τὸ πολὺ λεγομένων → grammar is a practical knowledge of the usage of poets and writers of prose
English (LSJ)
A one must walk or go, σοὶ β. πάρος S.El. 1502, Str.17.1.54; one must proceed, ἐπὶ τὸ καθόλου Arist.EN1180b21: pl., βαδιστέα Ar.Ach.394.