flagellum
noun
fla·gel·lum
flə-ˈje-ləm 
plural flagella
flə-ˈje-lə
also flagellums
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
Protein role in sperm development Inside every flagellum is an incredibly complex structure, including tiny components called radial spokes.
—
Mrigakshi Dixit, Interesting Engineering, 11 Sep. 2025
This means that the flagellum has a fool-proof mechanism to enable swimming in low viscosity environments, which would otherwise be impossible for aquatic species.
—Laura Baisas, Popular Science, 27 Sep. 2023
Microscopic examinations revealed the spore surface is lined with rows of proteins called rodlins that may grab a passing flagellum—working much like Velcro.
—Elizabeth Pennisi, Science | AAAS, 22 Mar. 2021
These organisms use a long, tail-like structure called a flagellum to move about.
—Scientific American, 30 Aug. 2019
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
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
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Mrigakshi Dixit, Interesting Engineering, 11 Sep. 2025
This means that the flagellum has a fool-proof mechanism to enable swimming in low viscosity environments, which would otherwise be impossible for aquatic species.
—Laura Baisas, Popular Science, 27 Sep. 2023
Microscopic examinations revealed the spore surface is lined with rows of proteins called rodlins that may grab a passing flagellum—working much like Velcro.
—Elizabeth Pennisi, Science | AAAS, 22 Mar. 2021
These organisms use a long, tail-like structure called a flagellum to move about.
—Scientific American, 30 Aug. 2019
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
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
Cite this Entry
“Flagellum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flagellum. Accessed 3 Nov. 2025.
Copy CitationKids Definition
flagellum
noun
fla·gel·lum
flə-ˈjel-əm
plural flagella
-ˈjel-ə
also flagellums
also flagellums
: a long whiplike structure by which some tiny plants and animals move
flagellar
adjective
-ˈjel-ər
Medical Definition
flagellum
noun
fla·gel·lum
flə-ˈjel-əm
plural flagella
-ə
also flagellums
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
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