# filament

/ˈfɪɫəmənt/ (US) · /fˈɪləmənt/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/filament
Updated: 2026-05-08

## Definition

a very thin wire or thread. You usually see this inside an old light bulb or as part of a flower.

For teachers: a slender, threadlike object or fibre, such as the wire in an incandescent lamp or the stalk of a stamen.

## Examples

- The light bulb stopped working because the filament broke.
- The 3D printer feeds a plastic filament through a heated nozzle to create the object layer by layer.
- In the early twentieth century, engineers experimented with various materials before discovering that a tungsten filament could withstand the high temperatures required for prolonged illumination.

## Usage notes

- Commonly used in technical contexts like electronics, 3D printing, and biology.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.