Source : Webster's Revised Unabridged Dictionary (1913)

Guilty \Guilt"y\, a. [Compar. {Gultier}; superl. {Guiltiest}.]
   [AS. gyltig liable. See {Guilt}.]
   1. Having incurred guilt; criminal; morally delinquent;
      wicked; chargeable with, or responsible for, something
      censurable; justly exposed to penalty; -- used with of,
      and usually followed by the crime, sometimes by the
      punishment.

            They answered and said, He is guilty of death.
                                                  --Matt. xxvi.
                                                  66.

            Nor he, nor you, were guilty of the strife.
                                                  --Dryden.

   2. Evincing or indicating guilt; involving guilt; as, a
      guilty look; a guilty act; a guilty feeling.

   3. Conscious; cognizant. [Obs.] --B. Jonson.

   4. Condemned to payment. [Obs. & R.] --Dryden.

Source : WordNet®

guiltiest
     See {guilty}

guilty
     adj 1: responsible for or chargeable with a reprehensible act; or
            marked by guilt; "guilty of murder"; "the guilty
            person"; "secret guilty deeds"; "a guilty conscience";
            "guilty behavior" [ant: {innocent}]
     2: showing a sense of guilt; "a guilty look"; "the hangdog and
        shamefaced air of the retreating enemy"- Eric Linklater
        [syn: {hangdog}, {shamefaced}, {shamed}]
     [also: {guiltiest}, {guiltier}]