The Collaborative International Dictionary of English v.0.48:

Rape \Rape\, n. [L. rapa, rapum, akin to Gr. "ra`pys, "ra`fys,
   G. r["u]be.] (Bot.)
   A name given to a variety or to varieties of a plant of the
   turnip kind, grown for seeds and herbage. The seeds are used
   for the production of rape oil, and to a limited extent for
   the food of cage birds.
   [1913 Webster]

   Note: These plants, with the edible turnip, have been
         variously named, but are all now believed to be derived
         from the Brassica campestris of Europe, which by some
         is not considered distinct from the wild stock
         (Brassica oleracea) of the cabbage. See Cole.
         [1913 Webster]

   Broom rape. (Bot.) See Broom rape, in the Vocabulary.

   Rape cake, the refuse remaining after the oil has been
      expressed from the rape seed.

   Rape root. Same as Rape.

   Summer rape. (Bot.) See Colza.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Broom rape \Broom" rape`\ (Bot.)
   A genus (Orobanche) of parasitic plants of Europe and Asia.
   They are destitute of chlorophyll, have scales instead of
   leaves, and spiked flowers, and grow attached to the roots of
   other plants, as furze, clover, flax, wild carrot, etc. The
   name is sometimes applied to other plants related to this
   genus, as Aphyllon uniflorumand Aphyllon Ludovicianum.
   [1913 Webster]