noun

fog

noun

A thick cloud of tiny water droplets close to the ground that reduces visibility.

"The fog was so thick we could barely see the road."

"Flights were delayed for hours because of dense fog."

A state of mental confusion or unclear thinking.

"She was still in a fog after the anesthesia wore off."

verb

To become covered in mist or condensation, or to make something unclear.

"The bathroom mirror fogged up after his shower."

"Grief fogged his judgment for weeks."

How to Use Fog

Learner’s notes

In plain EnglishA thick low cloud that blocks visibility, or a state of confused thinking; as a verb, to cover with mist or make unclear.

Common pairings

thick fog fog up in a fog fog rolled in

Word Forms

fogged past tense, fogged past tense, fogged past tense, fogs plural, fogs singular, fogs singular, fogs singular

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The _____ was so thick we could barely see the road.

Etymology

Origin uncertain, but probably linked to old North Germanic words for a squall or drifting spray, possibly related to a separate older English "fog" meaning tall marsh grass.