Definition of chloral in English:



mass noun
  • 1Chemistry
    A colourless, viscous liquid made by chlorinating acetaldehyde.

    Chemical formula: CCl₃CHO

    • ‘More preferably, the halogen-containing aldehyde, acetal or hemiacetal is selected from trichloroethanal, 2,2, 2-trichloro - 1-ethoxy ethanol and mixtures thereof.’
    • ‘When dissolved in water, trichloroethanal exists primarily in its hydrate form, chloral hydrate (commonly known as ‘knock-out drops’).’
    • ‘DDT is produced from the chlorobenzene and trichloroethanal (trichloroacetaldehyde or chloral), which react in the presence of concentrated sulfuric acid.’
    1. 1.1
      short for chloral hydrate
      • ‘Up to his neck in the reputedly healing waters, Daudet read Montaigne; and in private consumed huge amounts of morphine, chloral and bromide in an attempt to palliate his excruciating pains.’
      • ‘He had given up painting in 1878 and existed in the bohemian squalor of his Chelsea mansion, in a state of deep melancholy, sustained by a diet of 180 grains of chloral a day, washed down with whisky.’
      • ‘Depressed about losing Lucy, he considers taking chloral to sleep, but decides against it.’
      • ‘If chlorine gas is bubbled through ethanal, the hydrogen atoms of the methyl group are replaced by chlorine atoms to give chloral.’


Mid 19th century from French, blend of chlore ‘chlorine’ and alcool ‘alcohol’.