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• Legionella
  Legionella

  noun

  a genus of rod- or coccus-shaped aerobic Gram-negative bacteria, certain species of which, as L. pneumophila, produce legionnaires' disease.
• legionella
  legionella

  noun

  any Gram-negative rod-shaped bacterium of the genus Legionella, including L. pneumophila, which causes legionnaire's disease

Legionella

American  

[lee-juh-nel-uh] / ˌli dʒəˈnɛl ə /

noun

1. a genus of rod- or coccus-shaped aerobic Gram-negative bacteria, certain species of which, as L. pneumophila, produce legionnaires' disease.

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legionella British  

/ ˌliːdʒəˈnɛlə /

noun

1. any Gram-negative rod-shaped bacterium of the genus Legionella, including L. pneumophila, which causes legionnaire's disease

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Etymology

Origin of Legionella

< New Latin (1979), after legionnaires' disease; see -ella

Example Sentences

See Examples For:

Legionella legionella

Investigators found high levels of Legionella bacteria in a cooling tower at what was then the Embassy Suites Napa Valley on California Boulevard, Napa County health officials said.

From Los Angeles Times ● May 18, 2026

Legionella can grow and spread in devices such as hot tubs, cooling towers, hot water tanks, complex plumbing systems, showerheads, sink faucets and decorative fountains, according to the California Department of Public Health.

From Los Angeles Times ● May 18, 2026

The report noted that cooling towers can spread Legionella bacteria over a wide area, with people living within 0.6 miles from a tower at highest risk of infection.

From Los Angeles Times ● May 18, 2026

Legionnaires' disease is a lung infection most commonly contracted through the inhalation of water droplets containing Legionella bacteria.

From BBC ● Jun. 21, 2025

Following her diagnosis, the Greek health ministry issued a statement to hoteliers in Crete to "raise awareness among all those involved in monitoring the quality of water for human consumption especially with regard to Legionella".

From BBC ● Jun. 21, 2025

Legionnaires' disease, caused by the legionella bacteria, can result in a severe form of pneumonia.

From Reuters ● Sep. 14, 2023

Authorities are still checking how the legionella bacteria, which causes the disease, got into the water supply in the Rzeszow city and its surroundings.

From BBC ● Aug. 29, 2023

It's important not to set it any lower as it could create a health risk - legionella bacteria could develop in the water.

From BBC ● Dec. 11, 2022

Flint's water also contained trihalomethane, a carcinogen, as well as dangerous E. coli and legionella bacteria.

From Salon ● Nov. 26, 2021

In October, the facility brought in temporary showers and bottled water for more than a month after legionella bacteria, which can cause Legionnaires’ disease, was found in its water system.

From Washington Post ● Apr. 15, 2020