English Reference
Noun

filament

n. countable
C1 Advanced US /ˈfɪɫəmənt/ UK /fˈɪləmənt/ fil·a·ment UK spelling filament's, filament's Astronomy Botany Physics

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

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


SIMPLE

The light bulb stopped working because the filament broke.

CONTEXTUAL

The 3D printer feeds a plastic filament through a heated nozzle to create the object layer by layer.

COMPLEX

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

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

Rather, it breaks apart the membrane that covers jaw-muscle fibers, causing contractions strong enough to damage or destroy the muscle filaments that slide past each other when the muscles contract.

Ars Technica· 6 Aug 2026

Thick lanes of dust stand out as dark filaments because they are dense enough to resist being worn away, creating dramatic contrast against the glowing red clouds.

ScienceDaily· 5 Jul 2026

Borrowed from Medieval Latin fīlāmentum, from Late Latin fīlō (“to spin, draw out in a long line”), from Latin fīlum (“thread”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin fīlum
Level C1 · Advanced
Frequency Occasional
Updated