ἰχνεύειν

From LSJ

τούτου δὲ συμβαίνοντος ἀναγκαῖον γίγνεσθαι πάροδον καὶ τροπὰς τῶν ἐνδεδεμένων ἄστρων → but if this were so, there would have to be passings and turnings of the fixed stars

Source

Greek > English (Woodhouse Verbs Reversed)

(see also ἰχνεύω): track, scent out, track out