flagellum

noun

fla·​gel·​lum flə-ˈje-ləm How to pronounce flagellum (audio)
plural flagella flə-ˈje-lə How to pronounce flagellum (audio) also flagellums
: any of various elongated filiform appendages of plants or animals: such as
a
: the slender distal part of an antenna
b
: a long tapering process that projects singly or in groups from a cell and is the primary organ of motion of many microorganisms

Examples of flagellum 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.
These organisms use a long, tail-like structure called a flagellum to move about. — Scientific American, 30 Aug. 2019 Choanoflagellates live in seawater and use a tail, called a flagellum, to move through their environment and find food. — Nathaniel Scharping, Discover Magazine, 12 Jan. 2016 The most well known is the amoeba, but these microbes come in several forms, including species that move with a single flagellum or with hairlike cilia. — Adrian Higgins, idahostatesman, 23 Aug. 2017 Scientists in the 1980s and ’90s figured out that when the C ring rotates, the flagellum does too. — Quanta Magazine, 20 Apr. 2026 See All Example Sentences for flagellum

Word History

Etymology

New Latin, from Latin, whip, shoot of a plant

First Known Use

1852, in the meaning defined above

Time Traveler
The first known use of flagellum was in 1852

Rhymes for flagellum

See All Rhymes for flagellum

Browse Nearby Words

flagellin
flagellum
flageolet
See all Nearby Words

Cite this Entry

“Flagellum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flagellum. Accessed 7 Jul. 2026.

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Kids Definition

flagellum

noun
fla·​gel·​lum flə-ˈjel-əm How to pronounce flagellum (audio)
plural flagella -ˈjel-ə How to pronounce flagellum (audio) also flagellums
: a long whiplike structure by which some tiny plants and animals move
flagellar
-ˈjel-ər
adjective

Medical Definition

flagellum

noun
fla·​gel·​lum flə-ˈjel-əm How to pronounce flagellum (audio)
plural flagella -ə How to pronounce flagellum (audio) also flagellums
: a long tapering process that projects singly or in groups from a cell and is the primary organ of motion of many microorganisms

More from Merriam-Webster on flagellum

Britannica.com: Encyclopedia article about flagellum

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