smog

smog — noun

1. a thick, dirty haze in the air caused by pollution from cars, factories, and oth

1.nounB1
Definition

a thick, dirty haze in the air caused by pollution from cars, factories, and other sources; especially common in large cities and harmful to breathe.

Example

Ayesha could not see the mountains because thick smog had settled over the city.

collocation: thick smog

The government warned residents to wear masks when smog levels reached dangerous highs.

collocation: smog levels

Common collocations
  • thick smog
  • heavy smog
  • toxic smog
  • smog levels
  • smog warning
  • smog alert
  • smog clears
  • smog lifts
Synonyms
  • haze

    a broader term for any thin mist or vapor; haze may be natural (humidity) whereas smog always contains pollutants

  • pollution

    a general term for any harmful substances in the environment; smog is a specific visible type of air pollution

  • fog

    a natural weather phenomenon of thick water vapor near the ground; smog is fog-like but caused by human-made pollutants

Grammar Patterns

uncountable; cannot be used with 'a' or plural -s

Common Mistakes

The smog is a big problem in winter.
Smog is a big problem in winter.
smog is uncountable and does not take 'a' or 'the' for general reference.
There were thick smogs all week.
There was thick smog all week.
smog is uncountable; do not add a plural -s.

Word family

  • smoggy
    adjectiveB2

Synonym discussion

Sense: noun/1

Smog, haze, fog, and pollution all describe something that makes the air hard to see or breathe, but they differ in cause and scope. Smog is a visible, harmful blend of smoke and chemical pollutants, most common in crowded cities. Haze is a lighter, often natural mist from humidity or dust and may not be harmful. Fog is purely water vapor close to the ground — think of a misty morning in the countryside — and is rarely toxic. Pollution is the broadest term, covering any contaminant in air, water, or soil. Exhaust specifically refers to the gases released by a vehicle's engine and is one ingredient of smog rather than a type of smog itself. For example, 'thick smog forced the airport to cancel flights' describes a visibility hazard, while 'car exhaust contributes to the region's pollution problem' names one cause.

hazepollution ↗fog ↗exhaust ↗

Common collocations

Nouns

  • smog levels
  • smog warning
  • smog alert
  • smog pollution

Phrases

  • a blanket of smog
  • a layer of smog

Prepositions

  • in smog
  • through smog

Etymology

English (blend: smoke + fog)Old English: smoca (smoke) + fogga (fog)

Smog is a blend word formed by combining 'smoke' and 'fog'. It was first used in print in 1905 by Dr. Henry Antoine des Voeux in a report about London's air quality. The word quickly spread as industrial cities around the world struggled with coal-burning pollution, and it remains the standard term for the thick, polluted haze seen in many urban areas today.