rhizogen

Century Dictionary and Cyclopedia

1. n. A parasitic plant growing on the roots of other plants; specifically, a member of a division of plants (the class Rhizantheæ) proposed by Lindley, composed of flowering plants of a fungoid habit, parasitic upon rootstocks and stems. It embraced the present orders Balanophoreæ and Cytinaceæ, now regarded as belonging to the apetalous dicotyledons. The genus Rafflesia is an illustration.

Wiktionary

1. n. botany One of a proposed class of flowering plants growning on the roots of other plants and lacking green foliage.

GNU Webster's 1913

1. n. (Bot.) One of a proposed class of flowering plants growning on the roots of other plants and destitute of green foliage.