epidemic

epidemic — noun

1. a situation in which a contagious illness spreads rapidly across a community and

1.nounB2
Definition

a situation in which a contagious illness spreads rapidly across a community and infects many thousands of people in a short time

Example

Hassan noticed a flu epidemic spreading through his school in Taipei.

collocation: flu epidemic / measles epidemic

The city declared an emergency after a cholera epidemic broke out in the market.

collocation: epidemic + break out

Common collocations
  • flu / cholera / measles epidemic
  • epidemic breaks out / spreads / hits
  • declare / contain / control / slow an epidemic
Synonyms
  • outbreak

    more sudden and more localised; an outbreak can become an epidemic if it keeps spreading

  • pandemic

    much larger in scale — a pandemic affects multiple countries or the whole world

  • plague

    older term with religious or historical overtones; rarely used for modern diseases

Grammar Patterns

epidemic + of + disease name

an/the epidemic + verb (breaks out, spreads, hits)

Usage Note

Frequently paired with a prepositional phrase beginning with 'of' that names the specific disease (e.g., an epidemic of cholera).

Common Mistakes

The epidemic disease spread in the city.
The epidemic spread through the city.
'Epidemic' alone already refers to disease spread; adding 'disease' is redundant.

2. a serious social problem or negative trend that spreads rapidly and affects a ve

2.nounB2
Definition

a serious social problem or negative trend that spreads rapidly and affects a very large number of people in a society

Example

The city is facing an epidemic of loneliness among elderly residents.

collocation: an epidemic of [problem]

Trang's town has seen an epidemic of phone thefts on public buses.

Common collocations
  • an epidemic of violence / crime / obesity / loneliness / fake news
  • epidemic sweeping across [place]
  • face / struggle with an epidemic
Synonyms
  • crisis

    emphasises urgency and need for immediate action rather than scale of spread

  • scourge

    more dramatic and literary; suggests something that causes great suffering over a long period

Grammar Patterns

an epidemic of + (negative phenomenon)

epidemic + of + noun phrase

Usage Note

This sense extends the disease metaphor to social issues. The noun that follows 'epidemic of' must be negative or undesirable (crime, dishonesty, obesity, violence).

Common Mistakes

There is an epidemic of kindness in our town.
There is an epidemic of crime in our area.
This sense only works for negative or harmful trends, not positive ones.

epidemic — adjective

Word family

  • epidemiology
    nounC1
  • epidemiologist
    nounC1
  • epidemiological
    adjectiveC1

Synonym discussion

Sense: noun/1

All four words describe disease spreading, but they differ in scale and tone. An outbreak is the smallest and most sudden — a cluster of cases appearing in one place, like an outbreak of food poisoning at a wedding. An epidemic is larger, affecting many people across a community or region — a flu epidemic that sweeps through a city. A pandemic is an epidemic that crosses borders and affects the entire world, such as the COVID-19 pandemic. Plague is the most loaded term: it refers historically to the bubonic plague that killed millions, and is now used dramatically for any deadly, widespread disease or problem. In everyday use, choose outbreak for a localised event, epidemic for a regional health crisis, and pandemic for a global one.

epidemic ↗outbreak ↗pandemicplague ↗

Common collocations

Nouns

Adverbs

Phrases

  • reach epidemic levels / proportions
  • an epidemic sweeps across
  • declare an epidemic

Prepositions

Etymology

GreekLatinFrenchEnglish

Epidemic entered English in the early 1600s, borrowed from French épidémique, which came from the Latin epidēmia. The Latin word itself was taken from the Greek epidēmia, which combined epi- ('upon, among') and dēmos ('people'). So the word's original meaning — 'among the people' — already carried the idea of something circulating through a community. The disease sense became dominant after the great plagues of the 17th and 18th centuries, and the metaphorical use for social problems followed in the 1800s.