glass

Glass is a hard, brittle, and typically transparent material made by melting sand with other substances. It has been used for millennia—stretching from ancient Egyptian beads to the facades of modern skyscrapers! We most often think of glass as the substance used to make windows, bottles, and drinking vessels. For example: "She raised her glass in a toast."

But "glass" isn't limited to the physical material. It is frequently used to describe things that are delicate or easily broken in an emotional or metaphorical sense. To have a "heart of glass" implies being easily wounded, while a "glass jaw" is a common sports term for someone who cannot take a hit.

The term is also synonymous with extreme smoothness. The phrase "as smooth as glass" describes a surface—or an experience—that is effortless and seamless. Historically, the word was also a common term for a mirror, a usage that survives today in the phrase "looking-glass." In the plural form, "glasses" becomes an essential tool for vision.

Whether you're admiring its transparency, carefully handling its fragility, or enjoying a refreshing drink from a glass, it remains a surprisingly versatile word with a rich history and many layers of meaning.