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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Time Traveler for spirillum

The first known use of spirillum was circa 1875

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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

Rhyming Dictionary: Words that rhyme with spirillum

Britannica.com: Encyclopedia article about spirillum

Comments on spirillum

What made you want to look up spirillum? Please tell us where you read or heard it (including the quote, if possible).


to wander slowly or to speak indistinctly

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