Wiktionary
n. A heat-resistant glass made with the addition of boric oxide.
Wikipedia
Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low coefficients of thermal expansion (~3 × 10 K at 20 °C), making them resistant to thermal shock, more so than any other common glass. Such glass is less subject to thermal stress and is commonly used for the construction of reagent bottles. Borosilicate glass is sold under such trade names as Simax, Borcam, Borosil, Suprax, Kimax, Heatex, Endural, Schott, or Refmex, Kimble, and some (but not all) items sold under the trade name Pyrex (see PYREX details in History section below).
Usage examples of "borosilicate glass".
We will be coaxing Venetian and Thuringian glassmakers to make chemically resistant borosilicate glass, importing and refining Japanese zinc, and producing a variety of industrial chemicals.
The fluorescent ceiling panels are far too bright because borosilicate glass is worked at temperatures exceeding twenty-two hundred degrees Fahrenheit, it emits significant amounts of intense light that can damage anyone's eyes, not just mine.
You can't just order sheet mica (or rubber, or borosilicate glass, or gasoline, for that matter) over the phone or internet, and have it on your doorstep a few days later.