pyrex Pyrex • pyrexia · · · Info · Definitions · Characters · · pyrex · · Text Latin · · Script 5 · · Length Definitions · · · (noun) a borosilicate glass with a low coefficient of expansion; used for heat-resistant glassware in cooking and chemistry. Synonyms: Pyrex. · · Noun Definition 1 Characters · · e latin small letter e U+0065 p latin small letter p U+0070 r latin small letter r U+0072 x latin small letter x U+0078 y latin small letter y U+0079