assumption

noun

as·​sump·​tion ə-ˈsəm(p)-shən How to pronounce assumption (audio)
1
: a taking to or upon oneself
the assumption of a new position
2
: the act of laying claim to or taking possession of something
the assumption of power
3
a
: an assuming that something is true
a mistaken assumption
b
: a fact or statement (such as a proposition, axiom (see axiom sense 2), postulate, or notion) taken for granted
4
a
: the taking up of a person into heaven
b
capitalized : August 15 observed in commemoration of the Assumption of the Virgin Mary
5
: the taking over of another's debts
6

Examples of assumption in a Sentence

I made the assumption that he was coming, so I was surprised when he didn't show up. He will come home tomorrow. At least, that's my assumption. Many scientific assumptions about Mars were wrong. I'm telling you our arrival time on the assumption that you will check to see whether or not our flight is on time before you come to the airport. Her plan is based on the underlying assumption that the economy will improve in the near future. her assumption of the presidency the buyer's assumption of debt
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Science took longer to wade into the field, held back by the assumption that aging was inevitable. Alice Park, TIME, 11 Mar. 2025 This idea shines in Curiosity Collects More Customers, where Ridge explains that leaders must constantly challenge their own assumptions and seek fresh perspectives—whether from employees, customers, or even competitors. Nell Derick Debevoise, Forbes, 11 Mar. 2025 However, many professionals in the field are beginning to acknowledge that these requirements stem from outdated assumptions. Jesse Rhoades, The Conversation, 11 Mar. 2025 European countries are ditching their decades-old assumptions and becoming proactive players in their own right. Faisal Kutty, Newsweek, 11 Mar. 2025 See All Example Sentences for assumption

Word History

Etymology

Middle English, from Late Latin assumption-, assumptio taking up, from Latin assumere — see assume

First Known Use

13th century, in the meaning defined at sense 4a

Time Traveler
The first known use of assumption was in the 13th century

Browse Nearby Words

Cite this Entry

“Assumption.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/assumption. Accessed 14 Mar. 2025.

Kids Definition

assumption

noun
as·​sump·​tion ə-ˈsəm(p)-shən How to pronounce assumption (audio)
1
capitalized : August 15 observed as a church festival to mark the taking up of the Virgin Mary into heaven
2
a
: the act of taking upon oneself or taking possession of something
3
a
: the belief that something is true
b
: a fact or statement taken for granted

More from Merriam-Webster on assumption

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