A whiteout is when blowing snow makes it impossible to see anything around you. During a blizzard, if winds pick up enough fallen snow and swirl it through the air, everything becomes a wall of white: you can't see the road, nearby buildings, or even your own feet. It's like being inside a snow globe that someone just shook.

Whiteouts are genuinely dangerous. Drivers can become disoriented and crash because they lose all sense of direction. Hikers can wander in circles just a few feet from safety because they can't see landmarks. In Antarctica, researchers sometimes string ropes between buildings so they can feel their way back during whiteouts.

The term also describes something you might use at your desk: white-out (sometimes spelled with a hyphen) is a correction fluid that covers mistakes on paper. When you accidentally write the wrong word, you can paint over it with white-out and write the correct word once it dries. Before computers made editing easy, office workers and students relied heavily on bottles of this chalky white liquid to fix their typing and writing errors.