Cautionary means meant to serve as a warning. A cautionary tale, cautionary note, offered as a caution.
It appears mostly in the phrase cautionary tale, which is a story told because of what went wrong in it. The warning is the purpose, not a side effect — a sad story is not cautionary unless it is told to warn. Note caution beneath it.
1adjectivecautionaryMeant to serve as a warning.
“Her grandfather's gambling debts became a cautionary tale for the whole family.”
cautionary is a quality of purpose.
Medieval Latin
cautiōnārius
English, today
cautionary
Borrowed from Medieval Latin cautiōnārius.
Etymology from Wiktionary, CC BY-SA