Cloud vs Fog

When to use each in English, with meaning, register, and examples.

 CloudFog
MeaningA white or gray mass in the sky made of water or ice.A thick cloud of tiny water drops in the air that makes things hard to see.
CEFR levelA2-
Part of speechnoun
Usage notesUsed to describe the visible form of condensed water vapor in the atmosphere. Appropriate in both casual and formal contexts. Avoid using it metaphorically when talking about emotions unless discussing weather.Use 'fog' in both literal and metaphorical senses. In formal writing, avoid using 'fog' figuratively unless context allows.

Frequently asked questions: Cloud vs Fog

What's the difference between "Cloud" and "Fog"?

"Cloud" means: A white or gray mass in the sky made of water or ice. "Fog" means: A thick cloud of tiny water drops in the air that makes things hard to see.

When should I use "Cloud" and "Fog"?

They can all be used in everyday English.

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