noun

• (uncountable) A thick cloud that forms near the ground; the obscurity of such a cloud.
  "a bank of fog"
• (uncountable) A mist or film clouding a surface.
• (figurative) A state of mind characterized by lethargy and confusion.
  "He did so many drugs, he was still in a fog three months after going through detox."
• (photography) A silver deposit or other blur on a negative or developed photographic image.

verb

• (intransitive) To become covered with or as if with fog.
• (intransitive) To become obscured in condensation or water.
  "The mirror fogged every time he showered."
• (intransitive, photography) To become dim or obscure.
• (transitive, photography) To make dim or obscure.

noun

• (UK, dialect) Tall and decaying grass left standing after the cutting or grazing season.
  "[…] and they generally leave a great deal of Fog to rot on the Ground, which, with the Help of his well turned Dung-hill, dress his Ground […]"
• (Scotland) Moss.

verb

• (transitive) To pasture cattle on the fog (of), or aftergrass, of; to eat off the fog from (a field).
• (intransitive) To become covered with the kind of grass called fog.