tubercle bacillus


: a bacterium (Mycobacterium tuberculosis) that is a major cause of tuberculosis

Word History

First Known Use

1882, in the meaning defined above

Time Traveler
The first known use of tubercle bacillus was in 1882

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Cite this Entry

“Tubercle bacillus.” Dictionary, Merriam-Webster, Accessed 31 Jan. 2023.

Medical Definition

tubercle bacillus

: a bacterium of the genus Mycobacterium (M. tuberculosis) that causes tuberculosis in humans
also : a related mycobacterium (M. bovis) that causes tuberculosis in cattle and sometimes humans especially in underdeveloped countries

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