filaments

IPA/fˈɪləmənts/
KK[fˈɪləmənts]IPA/fˈɪləmənts/

filaments — noun

1. a very thin, flexible thread or fibre, either natural like silk or cotton, or ar

1.nounB2
Definition

a very thin, flexible thread or fibre, either natural like silk or cotton, or artificial like nylon or polyester, used in fabrics, industrial products, and biological structures.

Example

Nora pulled a single filament of silk from the spider's web to examine it under the microscope.

countable: a single filament of [material]

The jacket is padded with synthetic filaments that trap warm air close to the body.

collocation: synthetic filaments

Common collocations
  • synthetic filaments
  • natural filaments
  • muscle filaments
  • carbon filaments
  • a single filament
  • fine filament
Synonyms
  • fibre

    a broader term for natural or synthetic thread-like material; fibre can be a collection of filaments

  • strand

    more general; a strand of hair or rope can be thicker than a filament

  • thread

    usually refers to a twisted bundle of filaments used in sewing

Grammar Patterns

a filament of [material]

Usage Note

The singular form 'filament' is also common, especially when referring to a single strand: 'a filament of cotton'.

Common Mistakes

The fabric is made of thin threads called threads.
The fabric is made of thin strands called filaments.
'filament' is the specific term for a very fine, single strand, whereas 'thread' describes multiple twisted filaments.

2. a thin piece of metal wire inside a light bulb or heating element that produces

2.nounB2
Definition

a thin piece of metal wire inside a light bulb or heating element that produces light or heat when an electric current passes through it.

Example

When the bulb shattered, Takashi could see the tiny filament still glowing for a moment.

collocation: bulb filament

Old-fashioned incandescent bulbs use a tungsten filament, while LED bulbs work differently.

collocation: tungsten filament

Common collocations
  • tungsten filament
  • light bulb filament
  • carbon filament
  • broken filament
  • glowing filament
Synonyms
  • wire

    a general term for a metal conductor; wire is much broader and not specific to bulbs

  • heating element

    a broader term for the part that produces heat in appliances like toasters; may include a filament

Grammar Patterns

tungsten / carbon + filament

Usage Note

Frequently paired with 'tungsten' or 'carbon' to specify the metal. The word is less common for modern LED bulbs, which do not use a glowing filament.

Common Mistakes

I need to change the filament in my LED lamp.
I need to change the bulb in my LED lamp.
LED lamps do not contain a glowing wire filament.

3. a long, thin structure consisting of a single chain of cells or one very long ce

3.nounC1
Definition

a long, thin structure consisting of a single chain of cells or one very long cell, found in simple living things such as algae, fungi, and some bacteria.

Example

Amara examined the green filament of algae floating in the pond under the classroom microscope.

collocation: filament of algae

When bread mould grows, it first forms tiny white filaments that spread across the surface.

collocation: mould filaments

Common collocations
  • filament of algae
  • fungal filaments
  • bacterial filaments
  • green filament
  • long filament
Synonyms
  • hypha

    the specific term for a filament of a fungus; hyphae make up the mycelium

  • strand

    a more general, less technical term for a thread-like structure

  • trichome

    a technical term for a filament in certain algae and cyanobacteria

Grammar Patterns

filament of [organism]

Usage Note

Primarily a technical term in microbiology and botany. In everyday conversation, people are more likely to say 'strand' or 'thread' instead.

Common Mistakes

There are filaments growing on my old bread.
There is mould growing on my old bread.
'filament' is a scientific term; everyday speech uses 'mould' or 'fuzz'.

4. the thin, upright stalk of a flower's male reproductive part (the stamen) that h

4.nounC2
Definition

the thin, upright stalk of a flower's male reproductive part (the stamen) that holds the anther, which contains pollen.

Example

Diego carefully removed the filament and anther from the lily to study the parts of the flower.

part of a stamen in a flower

In tulips, the filaments are short and the anthers sit close to the petals.

Common collocations
  • filament of the stamen
  • stamen filament
  • long filament
  • short filament
Synonyms
  • stalk

    a more general term for any plant stem; less precise than 'filament' in botany

Grammar Patterns

filament of the stamen

Usage Note

A specialised botanical term. Learners studying plant biology should distinguish the filament from the style (part of the female pistil).

Common Mistakes

The filament of the flower holds up the petals.
The filament of the flower holds up the anther.
The filament supports the anther (the pollen-bearing part of the stamen), not the petals.

Word family

Synonym discussion

Sense: noun/1

Filament, fibre, strand, thread, and wire all describe long, thin objects, but they belong to different contexts. A filament is a very fine, flexible thread-like piece used in technical, electrical, or biological settings — for example, the glowing wire inside an old light bulb or the thread-like cells in algae. A fibre is a broader term for any natural or synthetic thread-like material, such as cotton fibre or dietary fibre; it can be made up of many filaments twisted together. A strand is a general word for a single piece of hair, rope, or similar object that is part of a larger whole: 'a strand of hair'. A thread is specifically a thin, twisted cord of filaments used in sewing. A wire is a metal conductor, thicker and more rigid than a filament. For example: 'He replaced the broken filament in the antique lamp' (not fibre or thread). 'She found a strand of hair on her jacket.'

fibre ↗strand ↗thread ↗wire ↗

Common collocations

Nouns

Phrases

  • a single filament
  • broken filament

Prepositions

  • filament of
  • filament in

Etymology

LatinEnglish

The word 'filament' comes from Latin 'filamentum', meaning 'a thread', which itself derives from 'filare' ('to spin, draw out into a thread') and ultimately from 'filum' ('thread'). It entered English in the late 1500s as a scientific term for fine threads found in nature, and later extended to artificial fibres and the glowing wire in electric bulbs.