acetylene

American  

[uh-set-l-een, -in] / əˈsɛt lˌin, -ɪn /

noun

Chemistry.

1. a colorless gas, C 2 H 2 , having an etherlike odor, produced usually by the action of water on calcium carbide or by pyrolysis of natural gas: used especially in metal cutting and welding, as an illuminant, and in organic synthesis.

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acetylene British  

/ əˌsɛtɪˈlɛnɪk, əˈsɛtɪˌliːn /

noun

1. Systematic name: ethyne.  a colourless flammable gas used in the manufacture of organic chemicals and in cutting and welding metals. Formula: C 2 H 2

2. 1. another name for alkyne

   2. ( as modifier )

      acetylene series

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acetylene Scientific  

/ ə-sĕt′l-ēn′,-ən /

1. A colorless, highly flammable or explosive gas with a characteristic sweet odor. It is used in welding torches and in the manufacture of organic chemicals such as vinyl chloride. Acetylene is the simplest alkyne, consisting of two carbon atoms joined by a triple bond and each attached to a single hydrogen atom. Also called ethyne. Chemical formula: C ₂ H ₂ .

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Other Word Forms

• acetylenic
  adjective

Etymology

Origin of acetylene

First recorded in 1860–65; acetyl + -ene

Example Sentences

To explore this effect, the researchers created carbon nanoparticles by igniting a mixture of argon and acetylene gas.

From Science Daily • Jan. 31, 2026

When it comes in contact with water, it produces acetylene gas, which is highly flammable and has damaging properties on health.

From BBC • Oct. 27, 2025

But an investigation by the California Dept. of Toxic Substances found containers of acetylene, a highly flammable gas, on site earlier this month.

From Los Angeles Times • Mar. 17, 2025

The Weisenbergs’ defense attorneys, Vicki Podberesky and Benjamin Gluck, argued their clients separated the offending acetylene canisters as soon as they were discovered and kept them away from machinery that could cause an explosion.

From Los Angeles Times • Mar. 13, 2025

Even though the bars were removed I could still see the jagged edges above and below the windows where they had been unevenly cut with an acetylene torch.

From "Hole in My Life" by Jack Gantos