/ Dictionary / Index A alyssum: Meaning and Definition of Find definitions for: a•lys•sum Pronunciation: (u-lis'um), [key] — n. any of various plants belonging to the genus Alyssum, of the mustard family, having clusters of small yellow or white flowers. any of several related plants of the genus Aurinia, as A. saxatilis, a widely cultivated species with yellow flowers. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: alyssum (Thesaurus) Alyson Alzheimer's disease Related Content Daily Word Quiz: tactful Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language