octane

 
Pronunciation: /ˈɒkteɪn/

noun

[mass noun] Chemistry
  • a colourless flammable hydrocarbon of the alkane series, present in petroleum spirit.
    • Chemical formula: C8H18; many isomers, especially the straight-chain isomer ( n-octane). See also isooctane

Origin:

late 19th century: from octo- 'eight' (denoting eight carbon atoms) + -ane2