/ Dictionary / Index P prostas: Meaning and Definition of Find definitions for: pro•stas Pronunciation: (prō'stas), [key] — pl. pro•sta•des (in classical architecture) an antechamber or vestibule. (in a classical temple) the area included between parastades. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. prostaglandin prostasis Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language