Source : Webster's Revised Unabridged Dictionary (1913)

Magnify \Mag"ni*fy\, v. i.
   1. To have the power of causing objects to appear larger than
      they really are; to increase the apparent dimensions of
      objects; as, some lenses magnify but little.

   2. To have effect; to be of importance or significance. [Cant
      & Obs.] --Spectator.

   {Magnifying glass}, a lens which magnifies the apparent
      dimensions of objects seen through it.

Magnify \Mag"ni*fy\, v. t. [imp. & p. p. {Magnified}; p. pr. &
   vb. n. {Magnifying}.] [OE. magnifien, F. magnifier, L.
   magnificare. See {Magnific}.]
   1. To make great, or greater; to increase the dimensions of;
      to amplify; to enlarge, either in fact or in appearance;
      as, the microscope magnifies the object by a thousand
      diameters.

            The least error in a small quantity . . . will in a
            great one . . . be proportionately magnified.
                                                  --Grew.

   2. To increase the importance of; to augment the esteem or
      respect in which one is held.

            On that day the Lord magnified Joshua in the sight
            of all Israel.                        --Joshua iv.
                                                  14.

   3. To praise highly; to land; to extol. [Archaic]

            O, magnify the Lord with me, and let us exalt his
            name together.                        --Ps. xxxiv.
                                                  3.

   4. To exaggerate; as, to magnify a loss or a difficulty.

   {To magnify one's self} (Script.), to exhibit pride and
      haughtiness; to boast.

   {To magnify one's self against} (Script.), to oppose with
      pride.

Source : WordNet®

magnify
     v 1: increase in size, volume or significance; "Her terror was
          magnified in her mind" [syn: {amplify}]
     2: to enlarge beyond bounds or the truth; "tended to
        romanticize and exaggerate this `gracious Old South'
        imagery" [syn: {overstate}, {exaggerate}, {overdraw}, {hyperbolize},
         {hyerbolise}, {amplify}] [ant: {understate}]
     3: make large; "blow up an image" [syn: {blow up}, {enlarge}]
        [ant: {reduce}]
     [also: {magnified}]