Date: 1500-1600
Origin: Probably from a Scandinavian language


1 noun
1 [uncountable and countable]DN cloudy air near the ground which is difficult to see through [= mist]
thick/dense/freezing fog
We got lost in the thick fog.
It will be a cold night, and there may be fog patches.
A blanket of fog covered the fields.
The fog lifted (=disappeared) in the afternoon.
2 [singular] informal a state in which you feel confused and cannot think clearly:
My mind was in a fog.
fog of
the fog of tiredness

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