Source : Webster's Revised Unabridged Dictionary (1913)

Imprudent \Im*pru"dent\, a. [L. imprudens; pref. im- not +
   prudens prudent: cf. F. imprudent. See {Prudent}, and cf.
   {Improvident}.]
   Not prudent; wanting in prudence or discretion; indiscreet;
   injudicious; not attentive to consequence; improper. --
   {Im*pru"dent*ly}, adv.

         Her majesty took a great dislike at the imprudent
         behavior of many of the ministers and readers.
                                                  --Strype.

Source : WordNet®

imprudent
     adj 1: not prudent or wise; "very imprudent of her mother to
            encourage her in such silly romantic ideas"; "would be
            imprudent for a noneconomist to talk about the details
            of economic policy"- A.M.Schlesinger [ant: {prudent}]
     2: lacking wise self-restraint; "an imprudent remark"