Process in which water vapor turns directly to a solid

This process is known as deposition and is the opposite of sublimation, hence why it is sometimes called desublimation

The reverse of deposition is sublimation and hence sometimes deposition is called desublimation. One example of deposition is the process by which, in sub-freezing air, water vapor changes directly to ice without first becoming a liquid ... This causes the water vapor to change directly into a solid.