vitrify

Imagine molten rock cooling so fast that it does not form normal crystals and instead becomes glassy, like obsidian. That is the basic idea of vitrifying: changing something into a glass-like solid. The word is often used in science too. For example, doctors and researchers can vitrify eggs, embryos, or other biological material by cooling them very quickly so ice crystals do not form and cause damage. In both cases, the idea is the same: something is changed into a hard, glass-like state.

To vitrify means to transform something into a glassy, amorphous (non-crystalline) solid—essentially turning it into a glass-like state. The word comes from the Latin vitrum, meaning "glass." While often associated with high temperatures and geological processes like volcanic eruptions, where molten rock cools so quickly that it doesn't form crystals, vitrification isn't limited to heat.

In science, particularly cryopreservation (the preservation of biological material), vitrifying involves rapidly cooling a substance—such as cells, tissues, or organs—to extremely low temperatures using cryoprotectants. This prevents the formation of ice crystals, which would otherwise expand and damage cellular structure. Think of it as solidifying something without allowing the liquid to turn into damaging ice. This process is used extensively in fertility treatments to preserve eggs and embryos, as well as in advanced stem cell research.

More loosely, "vitrify" can sometimes be used figuratively to describe emotional hardening. You might say someone's experiences "vitrified" their outlook on life, meaning they became rigid or emotionally distant after trauma.

Whether it is molten rock becoming obsidian, biological samples being preserved for the future, or an emotional state turning cold and hard—to vitrify is to transform something into a rigid, glass-like form, typically through a process of rapid change.