Definition of reductio ad absurdum in English:

reductio ad absurdum

noun

Philosophy
  • A method of proving the falsity of a premise by showing that its logical consequence is absurd or contradictory:

    ‘the argument is a reductio ad absurdum of utilitarianism’
    • ‘Indeed, this is going to be something of a reductio ad absurdum.’
    • ‘The argument that says no individual has power leads to a reductio ad absurdum.’
    • ‘Opposition to stem-cell research is the reductio ad absurdum of the right-to-life argument.’
    • ‘For some reason, this strikes me as the reductio ad absurdum of the whole project.’
    • ‘It's an entertaining reductio ad absurdum against those who complain about the unfairness of low-cost production by foreigners.’

Origin

Latin, literally reduction to the absurd.

Pronunciation

reductio ad absurdum

/rɪˌdʌktɪəʊ ad abˈsəːdəm/