What is the meaning of Whiteout?

A heavy snowstorm; a blizzard.

Any weather condition in which visibility and contrast are severely reduced by snow or sand causing the horizon and physical features of the terrain to disappear.

Correction fluid (from the brand name Wite-Out).

A sporting event where all in attendance are urged to wear white apparel.

The simulated erasure of a file, etc. on a read-only volume.

The suppression of a story by the media, analogously to deleting information with correction fluid.

The silencing of voices and perspectives other than those of white men.

Source: wiktionary.org