The Collaborative International Dictionary of English v.0.48:

Cautel \Cau"tel\, n. [F. caut[`e]le, L. cautela, fr. cavere to
   be on one's guard, to take care.]
   1. Caution; prudence; wariness. [Obs.] --Fulke.
      [1913 Webster]

   2. Craft; deceit; falseness. [Obs.] --Shak.
      [1913 Webster]