Definition of oleum in English:

oleum

noun

mass noun
  • A dense, corrosive liquid consisting of concentrated sulphuric acid containing excess sulphur trioxide in solution.

    ‘In Tennessee all officers undergo training in which they are exposed to both CS and oleum capsicum, and no significant injuries from exposure have been reported.’

Origin

Early 20th century from Latin, literally ‘oil’.

Pronunciation

oleum

/ˈəʊlɪəm/