teratoma

from WordNet (r) 3.0 (2006)

teratoma
    n 1: a tumor consisting of a mixture of tissues not normally
         found at that site

from The Collaborative International Dictionary of English v.0.48

Teratoma \Ter`a*to"ma\, n. [NL., fr. Gr. ?, ?, monster + -oma.]
   (Med.)
   A tumor, sometimes found in newborn children, which is made
   up of a heterigenous mixture of tissues, as of bone,
   cartilage and muscle.
   [1913 Webster]