/ Dictionary / Index P peridium: Meaning and Definition of Find definitions for: pe•rid•i•um Pronunciation: (pu-rid'ē-um), [key] — pl. -rid•e•a the outer enveloping coat of the fruit body in many fungi. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: peridium (Thesaurus) periderm peridot Related Content Daily Word Quiz: sublime Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language