Smog (noun)

A haze of smoke and other pollutants that obscures the clarity of the atmosphere.

Origin:

Formed by the combination of the words "smoke" and "fog".

Examples:

1. The city was covered in smog, making it hard to see the buildings.
2. The smog made it difficult to breathe, causing many people to wear masks.
3. The smog alert warned citizens to stay indoors.
4. The smog was caused by the local factory's pollution.
5. The smog cleared up after the wind blew it away.