Source : Webster's Revised Unabridged Dictionary (1913)

Diploid \Dip"loid\, n. [Gr. ? twofold + -oid.] (Crystallog.)
   A solid bounded by twenty-four similar quadrilateral faces.
   It is a hemihedral form of the hexoctahedron.

Source : WordNet®

diploid
     adj : of a cell or organism having two sets of chromosomes or
           twice the haploid number; "diploid somatic cells" [ant:
            {polyploid}, {haploid}]
     n : (genetics) an organism or cell having two sets of
         chromosomes or twice the haploid number