Lewis & Short

† 1. căballus, i, m., = καβάλλης [perh. Celtic; hence Ital. cavallo, Fr. cheval, Engl. cavalry, cavalier, etc.; cf. cob, Germ. Gaul], an inferior riding- or pack-horse, a nag (poet. and in post-Aug. prose): tardus, Lucil. ap. Non. p. 86, 15; Varr. ib.: mediā de nocte caballum Arripit, his nag, Hor. Ep. 1, 7, 88; so id. S. 1, 6, 59; 1, 6, 103; id. Ep. 1, 18, 36; Juv. 10, 60; 11, 195; Sen. Ep. 87, 8; Petr. 117, 12; Dig. 33, 7, 15: Gorgoneus, jestingly for Pegasus, Juv. 3, 118.

  1. B. Prov.
    1. 1. Optat ephippia bos piger, optat arare caballus, i.e. no one is content with his own condition, Hor. Ep. 1, 14, 43.
    2. 2. Tamquam caballus in clivo, for one who walks wearily, Petr. 134, 2 (cf. Ov. R. Am. 394: principio clivi noster anhelat equus).