/ Dictionary / Index P perigonium: Meaning and Definition of Find definitions for: per•i•go•ni•um Pronunciation: (per"i-gō'nē-um), [key] — pl. -ni•a the envelope of modified leaves surrounding the antheridia in mosses. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: perigonium (Thesaurus) perigon Périgord Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language