tube

tube — noun

1. A long hollow shape, typically made from materials such as metal, plastic, rubbe

1.nounB1
Definition

A long hollow shape, typically made from materials such as metal, plastic, rubber, or glass, used to carry or hold liquids and gases as they travel between locations.

Example

The plumber replaced the old metal tube under the kitchen sink.

tube as a physical pipe used in plumbing

Water flows through a narrow rubber tube connected to the washing machine.

Common collocations
  • metal tube
  • rubber tube
  • plastic tube
  • glass tube
  • bend a tube
Synonyms
  • pipe

    more rigid, typically metal or hard plastic, used for plumbing

  • hose

    flexible and usually attached to a tap for watering or washing

  • conduit

    formal or technical term for a channel that protects electrical wires

Usage Note

Often used interchangeably with 'pipe' for flexible or smaller conduits. 'Pipe' is more common for rigid metal plumbing fixtures.

Common Mistakes

The water runs through a tube in the wall.
The water runs through a pipe in the wall.
For rigid, fixed plumbing inside buildings, 'pipe' is the standard word; 'tube' usually refers to flexible or smaller conduits.

2. In medicine and biology, a narrow channel inside a living organism that transpor

2.nounB2
Definition

In medicine and biology, a narrow channel inside a living organism that transports fluids such as blood, air, or digestive substances from one part of the body to another.

Example

Food moves from the mouth to the stomach through a muscular tube called the oesophagus.

biological tube in the digestive system

Élise visited a doctor because one of her fallopian tubes was blocked.

Common collocations
  • fallopian tubes
  • bronchial tubes
  • Eustachian tube
  • blocked tube
  • narrow tube
Synonyms
  • duct

    technical term for a tube that carries secretions in the body

  • vessel

    specifically a blood vessel (not used for air passages)

  • passage

    less technical, broader meaning

Usage Note

Frequently appears in compound medical terms: 'fallopian tube', 'bronchial tube', 'Eustachian tube'. The plural form 'tubes' is common when referring to paired structures.

3. A soft, narrow container sealed at one end with a small opening at the other, ma

3.nounB1
Definition

A soft, narrow container sealed at one end with a small opening at the other, made of metal or plastic, designed to hold a thick liquid or paste that you push out by squeezing.

Example

Yumi squeezed out the last of the toothpaste before buying a new tube.

squeeze + out of the tube — indicating extracting contents

The artist bought a tube of red oil paint from the art supply shop.

Common collocations
  • tube of toothpaste
  • tube of paint
  • squeeze a tube
  • roll up a tube
  • cap of a tube
Synonyms
  • container

    more general; does not specify the squeezable design

  • tube packaging

    descriptive term for the packaging format

Usage Note

Nearly always followed by 'of' + substance: 'a tube of toothpaste / paint / hand cream / sunscreen'. The lid is screwed back on after each use to prevent the contents from drying out.

4. An informal British term for a metal can or glass bottle containing beer, typica

4.nounB2
Definition

An informal British term for a metal can or glass bottle containing beer, typically served cold.

Example

Imran opened a cold tube of beer while watching the football match.

informal: tube of beer = can or bottle of beer

After work, Matthew grabbed a couple of tubes from the fridge.

Common collocations
  • cold tube
  • tube of beer
  • grab a tube
  • open a tube
Synonyms
  • can

    neutral, not slang — the standard term across all varieties of English

  • tin

    British informal synonym for a can of beer

Usage Note

Chiefly British slang. Used in casual conversation, especially in pubs or among friends. 'A tube' means one can; 'a couple of tubes' is a common plural.

Common Mistakes

I bought a tube of beer from the shop.' (too formal/slow delivery)
I grabbed a tube from the shop.
The word 'tube' for beer is slang and works best in casual, short phrases.

5. An electric train network that runs mostly in tunnels beneath the streets of Lon

5.nounB1
Definition

An electric train network that runs mostly in tunnels beneath the streets of London, commonly referred to by locals as the Tube.

Example

Shanti took the Tube from King's Cross to Oxford Circus this morning.

the Tube + from [station] to [station] — typical route expression

Christopher has lived in London for five years but still gets lost on the Tube.

Common collocations
  • take the Tube
  • on the Tube
  • Tube station
  • Tube map
  • Tube line
  • Tube train
Synonyms

Usage Note

Always capitalised as 'the Tube' when referring to the London Underground. Use 'take the Tube' / 'go by Tube' / 'on the Tube'. The official name is 'the London Underground', but locals almost always call it 'the Tube' — the nickname comes from the shape of the deep-level tunnels, which are cylindrical tubes.

Common Mistakes

I went by tube to work.
I took the Tube to work.
Always use the definite article and capital 'T' when referring to the London system.

6. The television, considered as a device for watching programmes or as a broadcast

6.nounB2
Definition

The television, considered as a device for watching programmes or as a broadcast medium; used informally in phrases such as 'watch the tube' or 'on the tube'.

Example

After dinner, the whole family sat around watching the tube.

informal: watching the tube = watching TV

My grandfather still calls the television 'the tube' even though it is a flat screen.

Common collocations
  • on the tube
  • watch the tube
  • the small tube
Synonyms
  • TV

    neutral, more common in modern usage

  • television

    formal, the full word

  • the box

    British informal synonym, also old-fashioned

Usage Note

Informal and somewhat old-fashioned in American English, but still widely understood. Originates from the cathode-ray tube (CRT) used in older television sets. The definite article 'the' is required: 'on the tube', not 'on tube'.

Common Mistakes

What is on tube tonight?
What is on the tube tonight?
Always include 'the' before 'tube' in this sense.
Idioms

go down the tube/tubes

idiom

To fail completely or be ruined.

After the scandal, his political career went down the tubes.

Did the whole project go down the tubes when the funding stopped?

Word family

  • tubing
    nounB2
  • tubular
    adjectiveB2
  • tubeless
    adjectiveC1
  • inner tube
    nounB2

Synonym discussion

Sense: noun/1

Tube is the most general term for a hollow cylinder used to move liquids or gases — it covers everything from a flexible rubber garden tube to a rigid glass laboratory tube. Pipe is specifically used for rigid metal or plastic plumbing that carries water, gas, or sewage in buildings; you would say 'a burst pipe' but not 'a burst tube' in a house wall. Hose refers to a flexible tube attached to a tap or pump, typically used for watering gardens or washing cars, and often has a nozzle at the end. Conduit is a technical or formal term for a tube or channel that protects electrical wiring — it is rarely used for fluids. In everyday conversation, tube and pipe overlap most when talking about smaller kitchen or workshop items ('a cardboard tube', 'a copper pipe'), but pipe suggests permanence and tube suggests replaceability.

tube ↗pipe ↗hose ↗conduit

Common collocations

Nouns

  • water tube
  • air tube
  • gas tube
  • rubber tube
  • plastic tube
  • metal tube
  • toothpaste tube
  • paint tube

Phrases

  • a tube of something
  • in the tube
  • on the tube

Prepositions

  • through a tube
  • into a tube
  • out of a tube
  • inside a tube
  • along a tube

Etymology

LatinFrenchEnglish

The word 'tube' entered English from French, which borrowed it from Latin 'tubus', meaning 'pipe' or 'a hollow cylinder'. The sense for London's underground railway (the Tube) appeared in the early 1900s because the deep-level tunnels were constructed as circular iron tubes. The informal sense for television (the tube) arose in the mid-1900s as a reference to the cathode-ray tube — the large vacuum tube that formed the screen of older television sets.