assumption

[uh-suhmp-shuhn]

noun

1. something taken for granted; a supposition.

   a correct assumption.

   Synonyms: theory, postulate, guess, conjecture, hypothesis, presupposition

2. the act of taking for granted or supposing.

   Synonyms: presupposition, presumption

3. the act of taking to or upon oneself.

   Synonyms: acceptance

4. the act of taking possession of something.

   the assumption of power.

   Synonyms: usurpation, appropriation, seizure

5. arrogance; presumption.

   Synonyms: gall, forwardness, effrontery

6. the taking over of another's debts or obligations.

7. Ecclesiastical.

   1. (often initial capital letter),  the bodily taking up into heaven of the Virgin Mary.

   2. (initial capital letter),  a feast commemorating this, celebrated on August 15.

8. Logic.,  the minor premise of a syllogism.

assumption

¹

/ əˈsʌmpʃən /

noun

1. the act of taking something for granted or something that is taken for granted

2. an assuming of power or possession of something

3. arrogance; presumption

4. logic a statement that is used as the premise of a particular argument but may not be otherwise accepted Compare axiom

Assumption

²

/ əˈsʌmpʃən /

noun

1. the taking up of the Virgin Mary (body and soul) into heaven when her earthly life was ended

2. the feast commemorating this, celebrated by Roman Catholics on Aug 15

Other Word Forms

• assumptively adverb
• assumptive adjective
• misassumption noun
• nonassumption noun
• overassumption noun
• preassumption noun
• reassumption noun
• self-assumption noun
• superassumption noun

Word History and Origins

Origin of assumption¹

First recorded in 1250–1300; Middle English assumpcioun, assompcioun, assumsion, from Latin assūmptiōn- (stem of assūmptiō ), equivalent to assūmpt(us) “taken up” (past participle of assūmere ) + -iōn- noun suffix; assume, -ion

Word History and Origins

Origin of assumption¹

C13: from Latin assūmptiō a taking up, from assūmere to _assume

Example Sentences

A ruling could arrive before the end of the year, potentially disrupting the market’s assumptions for how high tariffs will be, and what products are affected, heading into 2026.

Read more on Barron's

The government has addressed the issue, with the Ministry of Justice announcing plans to repeal the assumption in October.

Read more on BBC

Their practices challenge modern assumptions about what counts as "development" and remind us that resilience often emerges from diversity: of species, of knowledge, and of cultural traditions.

Read more on Science Daily

But many livestock farmers are angry with the officials' assumption.

Read more on BBC

It won’t require students to accept assumptions that skew inquiry in favor of a certain position.

Read more on The Wall Street Journal

Related Words

• acceptance 
• belief 
• expectation 
• guess 
• hunch 
• hypothesis 
• inference 
• premise 
• presumption 
• supposition 
• suspicion 
• theory