/ Dictionary / Index R rootstock: Meaning and Definition of Find definitions for: root•stock Pronunciation: (rt'stok", root'-), [key] — n. a root and its associated growth buds, used as a stock in plant propagation. a rhizome. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rootstock (Thesaurus) rootstalk root test Related Content Daily Word Quiz: panacea Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language