Source : Webster's Revised Unabridged Dictionary (1913)

Immortality \Im`mor*tal"i*ty\, n.; pl. {Immortalities}. [L.
   immortalitas: cf. F. immortalit['e].]
   1. The quality or state of being immortal; exemption from
      death and annihilation; unending existance; as, the
      immortality of the soul.

            This mortal must put on immortality.  --1 Cor. xv.
                                                  53.

   2. Exemption from oblivion; perpetuity; as, the immortality
      of fame.

Source : WordNet®

immortality
     n 1: the quality or state of being immortal [ant: {mortality}]
     2: perpetual life after death