A Fog

1. (uncountable) A thick cloud that forms near the ground; the obscurity of such a cloud. (Compare mist, haze.) Synonyms: haze, mist
2. (uncountable) A mist or film clouding a surface. Synonym: steam
3. A state of mind characterized by lethargy and confusion.

Synonyms: daze, haze

4. (photography) A silver deposit or other blur on a negative or developed photographic image.
5. (computer graphics) Distance fog.

Usage notes

• To count sense thick cloud, bank of fog is usually used.
• To count sense clouding a surface, foggy patch is usually used.