'Rape root' definitions:

Definition of 'Rape root'

From: GCIDE

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]