Webster’s Revised Unabridged Dictionary · 1913
Cautionary
Cau′tion·a·ry (·ā·ry̆), a. 1. Conveying a caution, or warning to avoid danger; as, cautionary signals.
2. Given as a pledge or as security.
He hated Barnevelt, for his getting the cautionary towns out of his hands. Bp. Burnet.
3. Wary; cautious. [Obs.] Bacon.