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swine flu

American  
[swahyn floo] / ˈswaɪn ˈflu /

noun

Pathology.
  1. a form of influenza that afflicts pigs.

  2. a form of influenza that afflicts humans by infection with a virus once thought to be very similar to the influenza virus found in North American pigs.


swine flu Scientific  
/ swīn /
  1. A highly contagious form of influenza seen in swine, caused by a virus of the family Orthomyxoviridae. The infection is communicable to humans and caused a worldwide epidemic in 1918.


Etymology

Origin of swine flu

First recorded in 1920–25

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

There have been nine such declarations, including the Ebola outbreak in 2013, the COVID-19 pandemic, and the swine flu pandemic in 2009.

From MarketWatch May 17, 2026

In the spring of 2009, a shift happened with an H1N1 strain, also known as swine flu.

From Salon Jan. 8, 2026

During the flu season that ended in September, 280 children died from flu — the most since the swine flu pandemic season of 2009-10.

From Los Angeles Times Dec. 23, 2025

Ms Sturgeon agreed that the UK Influenza Pandemic Preparedness Strategy – produced in 2011 following the swine flu outbreak two years before – was inadequate to deal with Covid-19.

From BBC Jul. 18, 2024

It’s like they have the swine flu and are trying to avoid germs.

From "Love, Hate & Other Filters" by Samira Ahmed

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