mycobacterium

noun

my·​co·​bac·​te·​ri·​um ˌmī-kō-bak-ˈtir-ē-əm How to pronounce mycobacterium (audio)
: any of a genus (Mycobacterium) of nonmotile aerobic acid-fast bacteria that include numerous saprophytes and the pathogens causing tuberculosis and leprosy
mycobacterial
ˌmī-kō-bak-ˈtir-ē-əl How to pronounce mycobacterium (audio)
adjective

Examples of mycobacterium 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.
After stem cell treatments abroad, three Americans became infected by mycobacterium abscessus, a distant relative of the bacteria that cause tuberculosis and leprosy. — Eduardo Cuevas, USA TODAY, 9 May 2024 Three months later, in October 2023, the victim was diagnosed with a mycobacterium abscessus infection. — Charna Flam, Peoplemag, 3 May 2024

Word History

Etymology

New Latin

First Known Use

1909, in the meaning defined above

Time Traveler
The first known use of mycobacterium was in 1909

Rhymes for mycobacterium

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-mycin
mycobacterium
mycocecidium
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Cite this Entry

“Mycobacterium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mycobacterium. Accessed 31 Mar. 2025.

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Medical Definition

mycobacterium

noun
my·​co·​bac·​te·​ri·​um -ˈtir-ē-əm How to pronounce mycobacterium (audio)
1
capitalized : a genus of nonmotile acid-fast aerobic bacteria of the family Mycobacteriaceae that are usually slender and difficult to stain and that include the causative agents of tuberculosis (M. tuberculosis) and leprosy (M. leprae) as well as numerous purely saprophytic forms
2
plural mycobacteria -ē-ə How to pronounce mycobacterium (audio) : any bacterium of the genus Mycobacterium or a closely related genus
mycobacterial
-ē-əl How to pronounce mycobacterium (audio)
adjective

More from Merriam-Webster on mycobacterium

Britannica.com: Encyclopedia article about mycobacterium

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