Source : Webster's Revised Unabridged Dictionary (1913)

Cautious \Cau"tious\, a. [Cf. L. cautus, fr. caver. See
   {Caution}.]
   Attentive to examine probable effects and consequences of
   acts with a view to avoid danger or misfortune; prudent;
   circumspect; wary; watchful; as, a cautious general.

         Cautious feeling for another's pain.     --Byron.

         Be swift to hear; but cautious of your tongue. --Watts.

   Syn: Wary; watchful; vigilant; prudent; circumspect;
        discreet; heedful; thoughtful; scrupulous; anxious;
        careful.

   Usage: {Cautious}, {Wary}, {Circumspect}. A man is cautious
          who realizes the constant possibility of danger; one
          may be wary, and yet bold and active; a man who is
          circumspect habitually examines things on every side
          in order to weigh and deliberate. It is necessary to
          be cautious at all times; to be wary in cases of
          extraordinary danger; to be circumspect in matters of
          peculiar delicacy and difficulty.

Source : WordNet®

cautious
     adj 1: showing careful forethought; "reserved and cautious; never
            making swift decisions"; "a cautious driver" [ant: {incautious}]
     2: avoiding excess; "a conservative estimate" [syn: {conservative}]
     3: cautious in attitude and careful in actions; prudent; "a
        cautious answer"; "very cautious about believing
        everything she was told"
     4: unwilling to take risks

cautious
     n : people who are fearful and cautious; "whitewater rafting is
         not for the timid" [syn: {timid}] [ant: {brave}]