What does "caution" mean?

Caution: Security; guaranty; bail. [R.] The Parliament would yet give his majesty sufficient caution that the war should be prosecuted. Clarendon.

Additional senses

  1. 2.Precept or warning against evil of any kind; exhortation to wariness; advice; injunction. In way of caution I must tell you. Shak. Caution money, money deposited by way of security or guaranty, as by a student at an English university.
  2. 3.To give notice of danger to; to warn; to exhort [one] to take heed. You cautioned me against their charms. Swift.

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