Lewis Short
cautēla (noun F) : cautus, caveo (mostly post - class.)
* Caution, precaution.
* In gen.: si minus cum curā aut cautelā locus loquendi lectus est,Plaut. Mil. 3, 1, 6 dub. (bracketed by Brix); App. M. 2, p. 117, 7; 5, p. 160, 36.
* Esp., in the jurists, = cautio, a surety, security, Dig. 3, 3, 15; 13, 7, 6; 16, 3, 14.
Charlton T. Lewis, Charles Short, A Latin Dictionary