Lewis & Short

servŭlus (servŏl-), i (gen. plur. servulum, App. M. 4, 19), m. dim. [servus], a young slave, servant-lad, Plaut. Capt. 4, 2, 100; id. Men. 2, 2, 64; id. Poen. 1, 2, 58 al.; Ter. And. 1, 1, 56; id. Heaut. 1, 2, 17; 3, 1, 62 al.; Cic. Quint. 6, 27; Plin. Ep. 2, 17, 22; 3, 16, 8 al.
In apposition: homines servolos amare, etc., Plaut. Stich. 3, 1, 37.