The process of a substance changing directly from solid to vapor without going through a liquid phase is called sublimation.

Here are some examples of sublimation:

* Dry ice (solid carbon dioxide) sublimates at room temperature.

* Mothballs slowly disappear due to sublimation.

* Frozen water can sublimate in a vacuum or at very low temperatures.

The opposite process, where a vapor changes directly to a solid, is called deposition.