Source : Webster's Revised Unabridged Dictionary (1913)

Heterotopism \Het`er*ot"o*pism\, Heterotopy \Het`er*ot"o*py\, n.
   [Hetero- + Gr. ? place: cf. F. h['e]t['e]rotopie.]
   1. (Med.) A deviation from the natural position; -- a term
      applied in the case of organs or growths which are
      abnormal in situation.

   2. (Biol.) A deviation from the natural position of parts,
      supposed to be effected in thousands of years, by the
      gradual displacement of germ cells.