fil·​a·​ment | \ ˈfi-lə-mənt How to pronounce filament (audio) \

Definition of filament

: a single thread or a thin flexible threadlike object, process, or appendage (see appendage sense 2): such as
a : a tenuous (see tenuous sense 2) conductor (as of carbon or metal) made incandescent by the passage of an electric current specifically : a cathode (see cathode sense 2) in the form of a metal wire in an electron tube
b(1) : a thin and fine elongated constituent part of a gill (see gill entry 2 sense 1)
(2) : an elongated thin series of cells attached one to another or a very long thin cylindrical single cell (as of some algae, fungi, or bacteria)
c : the anther-bearing stalk of a stamen — see flower illustration

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Other Words from filament

filamentary \ ˌfi-​lə-​ˈmen-​t(ə-​)rē How to pronounce filamentary (audio) \ adjective
filamentous \ ˌfi-​lə-​ˈmen-​təs How to pronounce filamentous (audio) \ adjective

Synonyms for filament


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Examples of filament in a Sentence

algae covered with tiny filaments the cable was made up of fine filaments twisted together
Recent Examples on the Web One astonishing aspect of the wall is how big it is compared to the volume that the team was surveying: a contiguous filament of light 1.4 billion light-years long, packed into a cloud maybe 600 million in radius. Dennis Overbye, Star Tribune, "Vast wall of thousands of galaxies discovered in cosmos," 30 July 2020 Lewis Howard Latimer invented the carbon filament to allow lights to continuously shine. Aimee Lewis, CNN, "Handcuffs to light bulbs shine light on painful Black experience," 11 July 2020 The face shields Hernandez makes are done on an Artillery X1 printer using PLA filament. Jenna Schoenefeld, Popular Mechanics, "How Citizens Are Helping Healthcare Workers Fight the Coronavirus," 6 May 2020 For the medical equipment, library staff are using PLA filament from its stock for the ear savers and purchased plastic for the face shields, Woods said. Matt Kawahara,, "Librarians in San Mateo County use 3D printers to make equipment for health care workers," 22 Apr. 2020 His filament-poking kidney-cell experiments suggest that cell–cell contact is needed. Kendall Powell, Scientific American, "Survival of the Fittest Cells," 22 Jan. 2020 Teachers are often buying materials, like 3D printer filament, at their own expense. Erin Richards, USA TODAY, "Teacher Appreciation Week: They wanted respect. It only took a coronavirus pandemic and worldwide economic collapse.," 4 May 2020 One final note: Those steel filaments are very coarse and can be murder on your hands. Carla Lalli Music, Bon Appétit, "The Only Kitchen Scrubbing Pad That Matters Is Homax Steel Wool," 24 Mar. 2020 Down—the clusters of soft, fluffy filaments that keep a bird warm beneath its water- and wind-repelling feathers, rather than the feather themselves—holds loft to trap air and retain heat while still allowing moisture to wick away. Hayden Carpenter, Outside Online, "The Best Men's Midlayers on the Market Right Now," 11 Apr. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'filament.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of filament

1594, in the meaning defined above

History and Etymology for filament

Middle French, from Medieval Latin filamentum, from Late Latin filare to spin — more at file

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Time Traveler for filament

Time Traveler

The first known use of filament was in 1594

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Statistics for filament

Last Updated

10 Aug 2020

Cite this Entry

“Filament.” Dictionary, Merriam-Webster, Accessed 11 Aug. 2020.

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More Definitions for filament


How to pronounce filament (audio)

English Language Learners Definition of filament

: a thin thread or hair
: a thin wire in a light bulb that glows when electricity passes through it


fil·​a·​ment | \ ˈfi-lə-mənt How to pronounce filament (audio) \

Kids Definition of filament

1 : a fine thread a filament of silk
2 : a fine wire (as in a light bulb) that is made to glow by the passage of an electric current
3 : the stalk of a plant stamen that bears the anther


fil·​a·​ment | \ ˈfil-ə-mənt How to pronounce filament (audio) \

Medical Definition of filament

: a single thread or a thin flexible threadlike object, process, or appendage especially : an elongated thin series of cells attached one to another or a very long thin cylindrical single cell (as of some algae, fungi, or bacteria)

Other Words from filament

filamentous \ ˌfil-​ə-​ˈment-​əs How to pronounce filamentous (audio) \ adjective

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