\Hem"i*trope\, a. [Hemi- + Gr. ? to turn: cf. F.
h['e]mitrope.]
Half turned round; half inverted; (Crystallog.) having a
twinned structure.

\Hem"i*trope\, n.
That which is hemitropal in construction; (Crystallog.) a
twin crystal having a hemitropal structure.