Source : Webster's Revised Unabridged Dictionary (1913)

Intrinsic \In*trin"sic\ ([i^]n*tr[i^]n"s[i^]k), a. [L.
   intrinsecus inward, on the inside; intra within + secus
   otherwise, beside; akin to E. second: cf. F. intrins[`e]que.
   See {Inter-}, {Second}, and cf. {Extrinsic}.]
   1. Inward; internal; hence, true; genuine; real; essential;
      inherent; not merely apparent or accidental; -- opposed to
      {extrinsic}; as, the intrinsic value of gold or silver;
      the intrinsic merit of an action; the intrinsic worth or
      goodness of a person.

            He was better qualified than they to estimate justly
            the intrinsic value of Grecian philosophy and
            refinement.                           --I. Taylor.

   2. (Anat.) Included wholly within an organ or limb, as
      certain groups of muscles; -- opposed to {extrinsic}.

   {Intrinsic energy of a body} (Physics), the work it can do in
      virtue of its actual condition, without any supply of
      energy from without.

   {Intrinsic equation of a curve} (Geom.), the equation which
      expresses the relation which the length of a curve,
      measured from a given point of it, to a movable point, has
      to the angle which the tangent to the curve at the movable
      point makes with a fixed line.

   {Intrinsic value}. See the Note under {Value}, n.

   Syn: Inherent; innate; natural; real; genuine.

Intrinsic \In*trin"sic\, n.
   A genuine quality. [Obs.] --Warburton.

Source : WordNet®

intrinsic
     adj 1: belonging to a thing by its very nature; "form was treated
            as something intrinsic, as the very essence of the
            thing"- John Dewey [syn: {intrinsical}] [ant: {extrinsic}]
     2: situated within or belonging solely to the organ or body
        part on which it acts; "intrinsic muscles"