listeria

American  

[li-steer-ee-uh] / lɪˈstɪər i ə /

noun

Bacteriology.

1. any of several rod-shaped, aerobic, parasitic bacteria of the genus Listeria, pathogenic for humans and animals.

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listeria British  

/ lɪsˈtɪərɪə /

noun

1. any rodlike Gram-positive bacterium of the genus Listeria , esp L. monocytogenes , the cause of listeriosis

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Other Word Forms

• listerial
  adjective

Etymology

Origin of listeria

1960–65; < New Latin, named after J. Lister; see -ia

Explanation

Listeria is a bacteria that can contaminate food and make people very sick. In pregnant and elderly people, the infection caused by listeria is particularly dangerous. Infants and people with compromised immune systems are also especially vulnerable to listeriosis, the infection that the listeria bacteria can cause. The most serious cases can lead to blood infection and meningitis. Hand washing and thoroughly cooking raw food can help prevent the growth of listeria, and susceptible people can stay safe by avoiding certain foods, including soft cheese and raw hot dogs. Listeria is named in honor of the groundbreaking early 20th-century bacteriologist Joseph Lister.

Example Sentences

Soft cheeses made with such unpasteurized milk can run an infection risk from listeria bacteria, a special danger for pregnant women and newborns.

From Los Angeles Times • Feb. 14, 2026

Of course, safety issues abound in commercial dog food, too, where recalls for salmonella and listeria contamination are fairly common.

From The Wall Street Journal • Jan. 28, 2026

It is rare for food contaminated by listeria, a bacterium, to cause a very serious infection, known as listeriosis.

From BBC • Oct. 2, 2025

You might recognize the name listeria from the massive outbreak earlier this year linked to contaminated Boar’s Head meats.

From Salon • Aug. 6, 2025

The announcement identifies Listeria monocytogenes — commonly referred to as listeria — as the potential foodborne illness.

From Salon • Aug. 6, 2025