Lewis Short
fĭdĕjussor (noun M) : fidejubeo, jurid. t. t.
* One who gives security for any one, a bail, a surety under the most binding form known to the Roman law, Gai. Inst. 3, 115-127: De fidejussoribus,Just. Inst. 3, 20; Dig. 27, 7; 46, 1; Cod. Just. 5, 57; 8, 41; Ambros. de Tob. 12, 89; Vulg. Prov. 20, 16.
Charlton T. Lewis, Charles Short, A Latin Dictionary