fog

A thick cloud close to the ground that makes it difficult to see.

• Thick fog covered the road.
• The fog lifted before we left home.
• Flights were delayed because of dense fog.

Similar words: mist

Common phrases: thick fog, dense fog, fog lifts

A state in which you feel confused and cannot think clearly.

• I spent the morning in a fog.
• Lack of sleep left her in a mental fog.
• The fog in his mind slowly cleared.

How to use it: in a fog (After the long flight, I was in a fog.)

Similar words: confusion, haze

Opposites: clarity

Common phrases: in a fog, mental fog, brain fog

A thin cloudy layer on a surface that makes it hard to see through.

• There was fog on the mirror.
• She wiped the fog from her glasses.
• A layer of fog covered the inside of the window.

Similar words: mist, condensation

Common phrases: fog on glass, fog on something

To become covered with tiny drops of water that make glass difficult to see through.

• My glasses fog up in the kitchen.
• The bathroom mirror fogged after my shower.
• Why do the car windows keep fogging up?

How to use it: fog up (My glasses fog up when I enter a warm room.)

Similar words: mist up, steam up

Common phrases: fog up, fog over, glasses fog up

To cover something with a cloudy layer or thick cloud near the ground.

• Low clouds fog the valley each evening.
• The spray fogged the glass with a fine film.
• Drifting mist had fogged the view from the hill.

Similar words: cloud, obscure

Common phrases: fog something over, fog a lens

To make thoughts, facts, or an issue unclear or difficult to understand.

• Exhaustion can fog your judgment.
• The conflicting reports fogged the issue.
• Strong medication had fogged her memory of that evening.

Similar words: cloud, confuse, obscure

Opposites: clarify

Common phrases: fog the mind, fog someone’s judgment, fog the issue

To become covered by a cloudy layer or by thick cloud near the ground.

• The valley began to fog over.
• Coastal areas can fog over after sunset.
• By dawn, the view had fogged over completely.

Similar words: cloud over

Common phrases: fog over, fog up