δεκέμπριμος

From LSJ

κάμψαι διαύλου θάτερον κῶλον πάλινbend back along the second turn of the race, turning the bend and coming back for the second leg of the double run, run the homeward course, retrace one's steps

Source

Spanish (DGE)

-ου, ὁ lat. decemprimus, milit. decurión jefe de una turma de la caballería romana, Nil.M.79.348D, Lyd.Mag.1.46, cf. δεκάπρωτος 3.