Source : Webster's Revised Unabridged Dictionary (1913)

Caution \Cau"tion\, n. (Civil & Scots Law)
   A pledge, bond, or other security for the performance of an
   obligation either in or out of judicial proceedings; the
   promise or contract of one not for himself but another;
   security.

Caution \Cau"tion\ v. t. [imp. & p. p. {Cautioned}; p. pr. & vb.
   n. {Cautioning}.]
   To give notice of danger to; to warn; to exhort [one] to take
   heed.

         You cautioned me against their charms.   --Swift.

Caution \Cau"tion\, n. [F. caution a security, L. cautio, fr.
   cavere (For scavere) to be on one's guard, to take care
   (orig.) to be on the watch, see; akin to E. show.]
   1. A careful attention to the probable effects of an act, in
      order that failure or harm may be avoided; prudence in
      regard to danger; provident care; wariness.

   2. Security; guaranty; bail. [R.]

            The Parliament would yet give his majesty sufficient
            caution that the war should be prosecuted.
                                                  --Clarendon.

   3. 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.

   Syn: Care; forethought; forecast; heed; prudence;
        watchfulness; vigilance; circumspection; anxiety;
        providence; counsel; advice; warning; admonition.

Source : WordNet®

caution
     n 1: the trait of being cautious; being attentive to possible
          danger; "a man of caution" [syn: {cautiousness}, {carefulness}]
          [ant: {incaution}]
     2: a warning against certain acts; "a caveat against unfair
        practices" [syn: {caveat}]
     3: judiciousness in avoiding harm or danger; "he exercised
        caution in opening the door"; "he handled the vase with
        care" [syn: {precaution}, {care}, {forethought}]
     4: the trait of being circumspect and prudent [syn: {circumspection}]
     v : warn strongly; put on guard [syn: {admonish}, {monish}]