bird flu

noun

: avian influenza
specifically : severe often fatal influenza A caused by strains of a subtype (H5N1) of the causative orthomyxovirus (Alphainfluenzavirus influenzae) that have produced epidemics in domestic birds especially in Asia with sporadic associated human infections

Examples of bird flu in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Those worries make sense, and understanding how bird flu spreads and what to watch for is the best way to protect your flock and yourself. — Ryan Brennan, Miami Herald, 2 July 2026 Other illnesses, like bird flu, have also been transmitted to pets via commercial raw pet food. — Mary Walrath-Holdridge, USA Today, 9 June 2026 The first case of H5N1 bird flu has been confirmed in Australia, meaning the virus has now found its way to every continent. — Brie Stimson, FOXNews.com, 21 June 2026 On June 20 the strain of highly pathogenic bird flu that has killed wild birds and marine mammals on every other continent was confirmed in Australia for the first time. — John Drake, Forbes.com, 21 June 2026 See All Example Sentences for bird flu

Word History

First Known Use

1972, in the meaning defined above

Time Traveler
The first known use of bird flu was in 1972

Rhymes for bird flu

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Browse Nearby Words

bird flower
bird flu
bird font
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Cite this Entry

“Bird flu.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bird%20flu. Accessed 7 Jul. 2026.

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Medical Definition

bird flu

noun
ˈbərd- How to pronounce bird flu (audio)
: avian influenza
specifically : severe often fatal influenza A caused by strains of a subtype (H5N1) of the causative orthomyxovirus (Alphainfluenzavirus influenzae) that have produced epidemics in domestic birds especially in Asia with sporadic associated human infections

More from Merriam-Webster on bird flu

Britannica.com: Encyclopedia article about bird flu

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