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.
The California Department of Fish and Wildlife announced Wednesday that Jackie died from highly pathogenic avian influenza, also known as bird flu. — Iris Kwok, Los Angeles Times, 15 Oct. 2026 She was also diagnosed with Highly Pathogenic Avian Influenza (HPAI) commonly called bird flu, which was behind severe stomach ulceration. — Laura Baisas, Popular Science, 15 Oct. 2026 Per guidelines established to prevent the transmission of bird flu to wildlife or humans, Jackie’s remains were cremated. — Allison Gibson, Sacbee.com, 15 Oct. 2026 Her reporting has been pivotal to the world’s understanding of Covid-19, H5N1 bird flu, Ebola virus, measles, and even hantavirus. — Theresa Gaffney, STAT, 14 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 20 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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