Definition of flagellum in US English:


nounPlural flagella

  • A slender threadlike structure, especially a microscopic appendage that enables many protozoa, bacteria, spermatozoa, etc. to swim.

    • ‘A third group of bacteria has many flagella surrounding the cell.’
    • ‘The single flagellum provides the bacteria with mobility and kinetic activity.’
    • ‘Cilia and flagella are hairlike organelles extending from the cell surface.’
    • ‘This study was designed to learn how well the flagella of groups of bacteria might move fluid in a microscopic environment.’
    • ‘Development of the spermatid flagellum begins immediately after meiosis.’
    sprout, offshoot, scion, sucker, bud, spear, runner, tendril, sprig, cutting
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Early 19th century (denoting a whip or scourge): from Latin, diminutive of flagrum ‘scourge’.