Lewis & Short

Hămaxŏbĭi or -bĭoe, ōrum, m., = Ἁμαξόβιοι (living, going about in wagons), a Scythian people, Mel. 2, 1, 2; Plin. 4, 12, 25 (cf. Hor. C. 3, 24, 9; Just. 2, 2).
In sing.: Hamaxobio instabilior, Tert. adv. Marc. 1, 1.