mycobacterium

noun

my·​co·​bac·​te·​ri·​um ˌmī-kō-bak-ˈtir-ē-əm 

: 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 

adjective

Examples of mycobacterium in a Sentence

Recent Examples on the Web

Nontuberculous mycobacteria are found naturally in soil and water. — Ascend Agency, The Orlando Sentinel, 20 May 2026

Beyond providing critical questions to drive his science, this turn in Barry’s work toward immunology of mycobacteria launched his efforts to improve global health. — Marc Lipsitch, STAT, 30 Mar. 2026

The vast majority of people infected with TB have a latent form of the bacteria, mycobacterium tuberculosis, which remains dormant and non-transmissible — sometimes a hibernating infection can lie dormant for decades. — Chase Hunter, Mercury News, 31 Jan. 2026

Armadillos carry a high risk among game animals, as the species is known to be the only non-human species to carry mycobacterium leprae, the bacteria that causes leprosy, according to the Emerging Pathogens Institute at the University of Florida. — Stuart Dyos, USA Today, 29 Oct. 2025

Word History

Etymology

New Latin

First Known Use

1909, in the meaning defined above

Rhymes for mycobacterium

• magisterium
• ministerium
• agrobacterium
• corynebacterium
• bacterium
• delirium
• deuterium
• imperium
• puerperium
• venereum
• cyanobacterium

Medical Definition

mycobacterium

noun

my·​co·​bac·​te·​ri·​um -ˈtir-ē-əm 

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  : any bacterium of the genus Mycobacterium or a closely related genus

mycobacterial

-ē-əl 

adjective