pyrex

Short definition from Wiktionary

Noun

1. 1
   A kind of heat-resistant borosilicate glass, made by mixing a high concentration of boron oxides into the molten glass to reduce its thermal expansion coefficient.
2. 2
   Any borosilicate glass.
3. 3
   Any glass capable of withstanding high temperatures, such as tempered glass suitable for cooking.
4. 4
   Alternative form of pyrex.

Proper noun

1. 1
   A brand of glassware produced by the Corning corporation, capable of resisting high temperatures, and suitable for cooking applications, currently made with tempered glass.
2. 2
   A brand of glassware produced by Corning using borosilicate glass.