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.
When poultry test positive for this strain of bird flu, all nearby farms are quarantined and tested for the virus. — Nat Lash, ProPublica, 23 Oct. 2026 Animal health researchers are using related techniques to inoculate poultry against bird flu and cattle against foot-and-mouth disease. — Robert Kelly, Fortune, 22 Oct. 2026 In September 2025, bird flu was found at turkey farms in Le Sueur, Blue Earth and Stearns counties, weeks after the state's first detection since April in a Redwood County flock. — Wcco Staff, CBS News, 20 Oct. 2026 The costs of bird flu, instead, will be paid by consumers, vulnerable farmworkers, and most of all, the birds themselves. — Kenny Torrella, Vox, 20 Oct. 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 27 Oct. 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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