0 a weather condition in which very small drops of water come together to form a thick cloud close to the land or sea, making it difficult to see:
1 a confused or uncertain state, usually mentally or emotionally:
3 a mass of cloud consisting of small drops of water near the surface of the earth:
[ U ] Heavy fog made driving conditions dangerous.
Freezing fog and icy patches are expected to cause problems for motorists tonight.
As such, fog represents a very important hydrological input for this tropical seasonal rain forest.
Climatic conditions and tropical montane forest productivity: the fog has not lifted yet.
For laser anemometry, a 'micro-fog lubricator' was used to atomize oil particles of approximately 2pm diameter.