εὐθύγραμμος
From LSJ
ἤτοι ἐμοὶ τρεῖς μὲν πολὺ φίλταταί εἰσι πόληες Ἄργός τε Σπάρτη τε καὶ εὐρυάγυια Μυκήνη → The three cities I love best are Argos, Sparta, and Mycenae of the broad streets
English (LSJ)
ον, = foreg., Arist.Cael.286b13, al.; γωνία Oenopides ap. Procl.in Euc.p.333F., cf. Euc.1.44; τὸ εὐ. (with or without σχῆμα)
A rectilinear figure, Arist.APr.69a31, Pr.913b18, Thphr.HP1.12.1.