From Middle English assumpcioun, from Medieval Latin assumptio (a taking up (into heaven)) and Latin assumptio (a taking up, adoption, the minor proposition of a syllogism). Doublet of assumptio; see assume.


  • IPA(key): /əˈsʌm(p).ʃ(ə)n/[1][2][3]
  • (file)


assumption (countable and uncountable, plural assumptions)

  1. The act of assuming, or taking to or upon oneself; the act of taking up or adopting.
    His assumption of secretarial duties was timely.
  2. The act of taking for granted, or supposing a thing without proof; a supposition; an unwarrantable claim.
    Their assumption of his guilt disqualified them from jury duty.
  3. The thing supposed; a postulate, or proposition assumed; a supposition.
    • 1976, “The Journal of Aesthetic Education, Volume 10”, in (Please provide the book title or journal name)[1]:
      No doubt a finite evaluative argument must make some unargued evaluative assumptions, just as finite factual arguments must make some unargued factual assumptions.
  4. (logic) The minor or second proposition in a categorical syllogism.
  5. The taking of a person up into heaven.
  6. A festival in honor of the ascent of the Virgin Mary into heaven, celebrated on 15 August.
  7. (rhetoric) Assumptio.


Derived termsEdit

Related termsEdit


Further readingEdit


  1. ^ The Chambers Dictionary, 9th Ed., 2003
  2. ^ assumption”, in Lexico,; Oxford University Press, 2019–2022.
  3. ^ assumption”, in Merriam-Webster Online Dictionary