/ Dictionary / Index P Pyrex: Meaning and Definition of Find definitions for: Py•rex Pronunciation: (pī'reks), [key] — Trademark. Trademark. a brand name for any of a class of heat- and chemical-resistant glassware products of varying composition used for cooking. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: pyrex (Thesaurus) pyretotherapy pyrexia Related Content Daily Word Quiz: exemplary Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language