Breadcrumb Home > Dictionary > Index A agaricaceous: Meaning and Definition of Find definitions for: a•gar•i•ca•ceous Pronunciation: (u-gar"u-kā'shus), [key] — adj. belonging to the Agaricaceae, a family of fungi including mushrooms having blade-shaped gills on the underside of the cap. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. agaric agaric acid ✖ Related Content Daily Word Quiz: rocrustean Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language