trip·lo·blas·tic 
(trĭp′lō-blăstĭk)
(trĭp′lō-blăstĭk)adj.
Having body tissues derived from three germ layers, the endoderm, mesoderm, and ectoderm, seen in all multicellular animals except certain invertebrates such as the cnidarians and sponges.
[Greek triploos, triple; see pel-2 in the Appendix of Indo-European roots + -BLASTIC.]
trip′lo·blasty n.