Source : Webster's Revised Unabridged Dictionary (1913)

Isis \I"sis\, n. [L., the goddess Isis, fr. Gr. ?.]
   1. (Myth.) The principal goddess worshiped by the Egyptians.
      She was regarded as the mother of Horus, and the sister
      and wife of Osiris. The Egyptians adored her as the
      goddess of fecundity, and as the great benefactress of
      their country, who instructed their ancestors in the art
      of agriculture.

   2. (Zo["o]l.) Any coral of the genus Isis, or family
      {Isid[ae]}, composed of joints of white, stony coral,
      alternating with flexible, horny joints. See
      {Gorgoniacea}.

   3. (Astron.) One of the asteroids.

Source : WordNet®

Isis
     n : Egyptian goddess of fertility; daughter of Geb; sister and
         wife of Osiris

Source : Free On-Line Dictionary of Computing

ISIS
     
        1. A toolkit for implementing fault-tolerant distributed
        systems, developed at Cornell and now available commercially
     
        2. A dialect of {JOSS}.
     
        [Sammet 1969, p. 217].

IS-IS
     
        {Intermediate System-Intermediate System}