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1. quā̆drīgārĭus, a, um, adj. [quadrigae], of or belonging to a four-horse (racing) chariot (post-Aug.): quadrigario habitu, in the dress of the driver of a quadriga, Suet. Calig. 17: pulvis, for the race-horses, Veg. Vet. 1, 56; 2, 28, 19: FAMILIA, slaves who took care of the race-horses, Inscr. Grut. 339, 5.
Hence, as subst.: quā̆drīgārĭus, ii, m., one who drives a four-horse chariot in the circus, a chariot-racer (class.), Varr. R. R. 2, 7: in victoriā, Cic. Fragm. Or. in Toga Cand. ap. Ascon.; Suet. Ner. 16; Arn. 2, 70; Paul. ex Fest. p. 36, 12 Müll.
2. Quā̆drīgārĭus, ii, m., a Roman surname. Thus, Q. Claudius Quadrigarius, an old Roman historian, Vell. 2, 9, 6; Gell. 1, 7, 9; called simply Claudius, Liv. 8, 19, 13.