/ Dictionary / Index P pentecostarion: Meaning and Definition of Find definitions for: pen•te•cos•ta•ri•on Pronunciation: (pen"dē-kôs-tä'rē-ôn Eng. pen"ti-ko-stâr'ē-on"), [key] — pl. -cos•ta•ri•a -cos•ta•ri•ons. a service book of offices for the period from Easter to the Sunday after Pentecost. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Pentecostal Pentelicus Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language