presumption

American  

[pri-zuhmp-shuhn] / prɪˈzʌmp ʃən /

noun

• presumptions
  plural

1. the act of presuming.

2. assumption of something as true.

3. belief on reasonable grounds or probable evidence.

4. something that is presumed; an assumption.

5. a ground or reason for presuming or believing.

6. Law. an inference required or permitted by law as to the existence of one fact from proof of the existence of other facts.

7. an assumption, often not fully established, that is taken for granted in some piece of reasoning.

8. unwarrantable, unbecoming, or impertinent boldness.

   Synonyms:

   gall, arrogance, effrontery, audacity

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presumption British  

/ prɪˈzʌmpʃən /

noun

1. the act of presuming

2. bold or insolent behaviour or manners

3. a belief or assumption based on reasonable evidence

4. a ground or basis on which to presume

5. law an inference of the truth of a fact from other facts proved, admitted, or judicially noticed

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Other Word Forms

Derived Forms

• overpresumption
  noun

Inflected Forms

Nouns

• presumptions
  plural

Etymology

Origin of presumption

1175–1225; Middle English: effrontery, supposition < Latin praesūmptiōn- (stem of praesūmptiō ) anticipation, supposition, Late Latin: presumptuousness, equivalent to praesūmpt ( us ) (past participle of praesūmere to undertake beforehand; see presume) + -iōn- -ion

Explanation

The noun presumption pretty much means jumping to conclusions. It is taking something for granted — an idea, an answer, an event — without having any real knowledge about it, and that is usually not a good thing. Making a presumption means assuming something is true or false without getting all the information necessary for verification. You can decipher this from the prefix pre, which means "before," together with the sume — from the Latin sumere, "to take." Because so many times a presumption turns out to be false, the word has a negative connotation to it; there's something reckless about making up your mind before you know all the facts.

Example Sentences

See Examples For:

presumption presumptions

Prosecutors say the presumption of innocence still applies, even after a suspect's death, and they have also said there is no reliable evidence to suggest anyone else was involved in the attack.

From BBC ● Aug. 20, 2026

There have been more leaks to the media than I've ever seen as a journalist and Ahmadzai's defence lawyer highlighted that this could be to the detriment of his presumption of innocence.

From BBC ● Aug. 7, 2026

Halstead was disappointed: “The fact of the convention was the defeat of Seward rather than the nomination of Lincoln. It was the triumph of a presumption of availability over pre-eminence in intellect and unrivaled fame.”

From The Wall Street Journal ● Jul. 31, 2026

The DOJ invoked the presumption of regularity and argued his arrest was part of an anti-terrorism dragnet, which the judge threw out.

From Salon ● Jul. 30, 2026

The presumption in those practice sessions was that he'd be rescuing a crewmate whose tether had broken, but the principle was the same.

From "The Martian" by Andy Weir

So it's perhaps no surprise that now he appears to have at least an outside chance of making a fist of it, he is not making any presumptions.

From BBC ● Aug. 23, 2026

“Viewed positively, what the American revolution did was to give the common man a voice, a veto, elbow room and a refuge from the rampaging presumptions of his ‘betters.’

From The Wall Street Journal ● May 19, 2026

With this first season, Hawley has given us an excellent tale about colonization that covers space, Earth, and body sovereignty, cautioning against presumptions of superiority.

From Salon ● Sep. 24, 2025

“It’s problematic in terms of just continuing to add rebuttable presumptions to workers’ comp law when you don’t really need it and Cal/OSHA is already moving to address the problem.”

From Los Angeles Times ● Sep. 12, 2024

I had discarded my presumptions that graduates automatically became leaders and that my connection to the Thembu royal house guaranteed me respect.

From "Long Walk to Freedom" by Nelson Mandela

Related Words

• assumption
• likelihood
• premise
• supposition
• suspicion