plural listeria
: any of a genus (Listeria) of small, gram-positive, rod-shaped bacteria that do not form spores and have a tendency to grow in chains and that include one (Listeria monocytogenes) that causes listeriosis
A common germ found in many foods from raw vegetables to hot dogs, listeria can cause a sometimes fatal disease called listeriosis when present in large quantities.Amy Barrett
also : a disease or sickness caused by infection with this bacterium : listeriosis
Listeria symptoms include high fever, severe headache, stiffness, nausea, abdominal pain and diarrhea. Sierra Brown

Examples of listeria 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.
Frozen pasta is being recalled due to potential contamination from listeria. Julia Hawkins, Sacbee.com, 17 Sep. 2026 Two lots of Walmart store brand frozen pasta have been recalled after testing by the Departments of Agriculture in Florida and Washington state found listeria. David J. Neal, Miami Herald, 17 Sep. 2026 Those who contract an intestinal illness from listeria can also develop diarrhea and vomiting. Julia Gomez, USA Today, 9 Sep. 2026 During a routine import reinspection sample testing, a product was confirmed positive for listeria monocytogenes, the recall says. Susan Selasky, Freep.com, 8 Sep. 2026 See All Example Sentences for listeria

Word History

Etymology

New Latin, from Listeria, from Joseph Lister

First Known Use

1952, in the meaning defined above

Time Traveler
The first known use of listeria was in 1952

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Cite this Entry

“Listeria.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/listeria. Accessed 19 Sep. 2026.

Medical Definition

listeria

noun
1
capitalized : a genus of small gram-positive flagellated rod-shaped bacteria that do not form spores, are aerobic or facultatively anaerobic, and have a tendency to grow in chains and that include one (L. monocytogenes) causing listeriosis
2
: any bacterium of the genus Listeria

called also listerella

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