Source : Webster's Revised Unabridged Dictionary (1913)

Inform \In*form"\, a. [L. informis; pref. in- not + forma form,
   shape: cf. F. informe]
   Without regular form; shapeless; ugly; deformed. --Cotton.

Inform \In*form"\, v. t. [imp. & p. p. {Informed}; p. pr. & vb.
   n. {Informing}.] [OE. enformen, OF. enformer, F. informer. L.
   informare; pref. in- in + formare to form, share, fr. forma
   form. See {Form}.]
   1. To give form or share to; to give vital ororganizing power
      to; to give life to; to imbue and actuate with vitality;
      to animate; to mold; to figure; to fashion.

            ``The informing Word.''               --Coleridge.

            Let others better mold the running mass Of metals,
            and inform the breathing brass.       --Dryden.

            Breath informs this fleeting frame.   --Prior.

            Breathes in our soul,informs our mortal part.
                                                  --Pope.

   2. To communicate knowledge to; to make known to; to
      acquaint; to advise; to instruct; to tell; to notify; to
      enlighten; -- usually followed by of.

            For he would learn their business secretly, And then
            inform his master hastily.            --Spenser.

            I am informed thoroughky of the cause. --Shak.

   3. To communicate a knowledge of facts to,by way of
      accusation; to warn against anybody.

            Tertullus . . . informed the governor against Paul.
                                                  --Acts xxiv.
                                                  1.

   Syn: To acquaint; apprise; tell; teach; instruct; enlighten;
        animate; fashion.

Inform \In*form"\, v. t.
   1. To take form; to become visible or manifest; to appear.
      [Obs.]

            It is the bloody business which informs Thus to mine
            eyes.                                 --Shak.

   2. To give intelligence or information; to tell. --Shak.

            He might either teach in the same manner,or inform
            how he had been taught.               --Monthly Rev.

   {To inform against}, to communicate facts by way of
      accusation against; to denounce; as, two persons came to
      the magistrate, and informed against A.

Source : WordNet®

inform
     v 1: impart knowledge of some fact, state or affairs, or event
          to; "I informed him of his rights"
     2: give character or essence to; "The principles that inform
        modern teaching"
     3: act as an informer; "She had informed on her own parents for
        years"