/ Dictionary / Index R rootlet: Meaning and Definition of Find definitions for: root•let Pronunciation: (rt'lit, root'-), [key] — n. Bot. a little root. a small or fine branch of a root. one of the adventitious roots by which ivy or the like clings to rocks or other supports. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rootlet (Thesaurus) rootless root mean square Related Content Daily Word Quiz: penury Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language