spi·​ril·​lum | \ spī-ˈri-ləm How to pronounce spirillum (audio) \
plural spirilla\ spī-​ˈri-​lə How to pronounce spirilla (audio) \

Definition of spirillum

: any of a genus (Spirillum) of curved elongated motile bacteria having tufts of flagella at both poles broadly : a spiral filamentous bacterium (such as a spirochete)

First Known Use of spirillum

circa 1875, in the meaning defined above

History and Etymology for spirillum

New Latin, from diminutive of Latin spira coil

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The first known use of spirillum was circa 1875

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Cite this Entry

“Spirillum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spirillum. Accessed 26 Nov. 2020.

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More Definitions for spirillum


spi·​ril·​lum | \ spī-ˈril-əm How to pronounce spirillum (audio) \

Medical Definition of spirillum

1 capitalized : a genus of gram-negative bacteria comprising elongated forms having tufts of flagella at both poles and usually living in stagnant water rich in organic matter — see rat-bite fever sense b
2 plural spirilla\ -​ˈril-​ə How to pronounce spirilla (audio) \ : any bacterium of the genus Spirillum

More from Merriam-Webster on spirillum

Britannica.com: Encyclopedia article about spirillum

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