Source : Webster's Revised Unabridged Dictionary (1913)

Guard \Guard\, v. t. [imp. & p. p. {Guarded}; p. pr. &, vb. n.
   {Gurding}.] [OF. guarder, garder, warder, F. garder, fr. OHG.
   wart?n to be on the watch, await, G. marten. See {Ward}, v. &
   n., and cf. {Guard}, n.]
   1. To protect from danger; to secure against surprise,
      attack, or injury; to keep in safety; to defend; to
      shelter; to shield from surprise or attack; to protect by
      attendance; to accompany for protection; to care for.

            For Heaven still guards the right.    --Shak.

   2. To keep watch over, in order to prevent escape or restrain
      from acts of violence, or the like.

   3. To protect the edge of, esp. with an ornamental border;
      hence, to face or ornament with lists, laces, etc.

Guarded \Guard"ed\, a.
   Cautious; wary; circumspect; as, he was guarded in his
   expressions; framed or uttered with caution; as, his
   expressions were guarded. -- {Guard"edly}, adv. --
   {Guard"ed*ness}, n.

Source : WordNet®

guarded
     adj 1: very reluctant to give out information [syn: {noncommittal},
             {unrevealing}]
     2: prudent; "guarded optimism" [syn: {restrained}]