assume

American  

[uh-soom] / əˈsum /

verb (used with object)

• assumes,
  present (3rd person singular)
• assumed,
  past participle,  past
• assuming
  present participle

1. to take for granted or without proof.

   to assume that everyone wants peace.

   Synonyms:

   posit, postulate, presuppose, suppose

2. to take upon oneself; undertake.

   to assume an obligation.

3. to take over the duties or responsibilities of.

   to assume the office of treasurer.

4. to take on (a particular character, quality, mode of life, etc.); adopt.

   He assumed the style of an aggressive go-getter.

5. to take on; be invested or endowed with.

   The situation assumed a threatening character.

6. to pretend to have or be; feign.

   to assume a humble manner.

7. to appropriate or arrogate; seize; usurp.

   to assume a right to oneself; to assume control.

8. to take upon oneself (the debts or obligations of another).

9. Archaic. to take into relation or association; adopt.

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verb (used without object)

• assumes,
  present (3rd person singular)
• assumed,
  past participle,  past
• assuming
  present participle

1. to take something for granted; presume.

assume British  

/ əˈsjuːm /

verb

1. (may take a clause as object) to take for granted; accept without proof; suppose

   to assume that someone is sane

2. to take upon oneself; undertake or take on or over (a position, responsibility, etc)

   to assume office

3. to pretend to; feign

   he assumed indifference, although the news affected him deeply

4. to take or put on; adopt

   the problem assumed gigantic proportions

5. to appropriate or usurp (power, control, etc); arrogate

   the revolutionaries assumed control of the city

6. Christianity (of God) to take up (the soul of a believer) into heaven

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Usage

What's the difference between assume and presume? Assume and presume have very similar meanings—they both mean to suppose that something is true without being able to confirm it. Assume, however, usually implies that the conclusion reached by the person doing the assuming is not based on much. Presume, on the other hand, often implies that the conclusion is based on something a bit stronger, such as some evidence or past situations in which the same thing happened. For example, you might presume that someone will be attending a meeting because they always attend and you have no reason to think they won’t be there. The word assume could also be used in this scenario, but it’s most likely to be used in situations in which there was less of a reason to have come to a certain conclusion. For example, you might assume something about someone you’ve just met based only on how they look (which is never a good idea). A good way to remember this difference in how the two words are used is that the prefix pre- in presume means “before”—when you presume things, you’re often basing that presumption on something that has happened before. As for assume, well, we’ll just assume you know a good way of remembering how it’s used. Assume and presume also have a few meanings that don’t overlap. Assume can mean to take on, adopt, or be endowed with something, as in I don’t want to assume any new responsibilities. Presume can mean to undertake or do something without permission or justification, as in I don’t presume to speak for the entire class. Here are examples of assume and presume used correctly in a sentence. Example: I assumed you knew what you were doing when you volunteered to bake the cake, but apparently I shouldn’t have. Example: I presumed, based on your resume, that you knew how to work with this software. Want to learn more? Read the full breakdown of the difference between assume and presume.

Synonym Usage

See pretend.

Other Word Forms

Derived Forms

• assumer
  noun
• overassume
  verb (used with object)
• preassume
  verb (used with object)
• reassume
  verb (used with object)
• assumable
  adjective

Inflected Forms

Participles

• assuming
  present
• assumed
  past

Conjugated Forms

Present

• assume
  simple
• assumes
  simple
• have assumed
  perfect
• has assumed
  perfect
• am assuming
  progressive
• are assuming
  progressive
• is assuming
  progressive
• have been assuming
  perfect progressive
• has been assuming
  perfect progressive

Past

• assumed
  simple
• had assumed
  perfect
• was assuming
  progressive
• were assuming
  progressive
• had been assuming
  perfect progressive

Future

• will assume
  simple
• will have assumed
  perfect
• will be assuming
  progressive
• will have been assuming
  perfect progressive

Etymology

Origin of assume

First recorded in 1400–50; late Middle English (from Anglo-French assumer ), from Latin assūmere “to take to, adopt,” equivalent to as- “toward” + sūmere “to take up”; see as-, consume

Explanation

Assume isn't only used to mean "accept as truth without checking"; it also means "take on the form of." It might be safer if you don't assume that the vampire standing in front of you isn't merely a person assuming that form. Assume always has the sense of taking on something. It may be the belief in the appearance of truth: Your mother probably assumes you do your homework right after school. It may be another form or identity: Superman assumes the identity of a city reporter. Or, it might be a physical space: If you get nervous while driving, your dad might assume control of the car.

Example Sentences

See Examples For:

assume assumes assumed assuming

One might assume that three talented artists with “Womack” and “Cooke” attached to their names would have an easy path, but that wasn’t the case for the Womack Sisters.

From Los Angeles Times ● Aug. 17, 2026

It’s perfectly reasonable for Claude to underestimate its own abilities and assume it can’t do certain things—because until recently, it couldn’t.

From The Wall Street Journal ● Aug. 15, 2026

Do not assume that writing a check back to the employer will erase the income when it comes to your ACA subsidy.

From MarketWatch ● Aug. 14, 2026

"When we see something very red in the universe, we often assume that it is surrounded by dust, like soot or ash," Simcoe explains.

From Science Daily ● Aug. 13, 2026

I’m about to complement her shirt, when the girl I assume is Emma crosses her arms and raises one eyebrow.

From "South of Somewhere" by Kalena Miller

“I’m a regular person, like you,” Hal says, gazing directly through the fourth wall at the tiny people he assumes are worshipping him from afar.

From Salon ● Aug. 14, 2026

The original incorrectly said Macquarie “forecasts no dividend and assumes roughly A$1.8 billion in growth capital expenditure.”

From The Wall Street Journal ● Aug. 6, 2026

The company’ aggressive sales-growth goal assumes it will continue to make acquisitions.

From MarketWatch ● Jul. 27, 2026

Southwest said its new profit guidance is based on the forward fuel curve as of July 17, and assumes the current fare environment and demand trends remain intact.

From The Wall Street Journal ● Jul. 22, 2026

And how easily she assumes they can get permission from Papa.

From "In the Time of the Butterflies" by Julia Alvarez

For decades, scientists generally assumed that fossilization destroyed the original organic molecules once present in bones, teeth, and other tissues.

From Science Daily ● Aug. 14, 2026

Her fans, some “who knew something was terribly wrong but assumed she had cancer or some other disease,” were aghast at her appearance whenever she took the stage.

From Salon ● Aug. 13, 2026

“I assumed it was part of the audition process,” she says.

From Los Angeles Times ● Aug. 12, 2026

“A higher trade-in value in the U.S. could drive stronger demand for the iPhone 17, but create more pressure on iPhone 18 sales given limited feature upgrades but assumed mid-teen % price hikes.”

From The Wall Street Journal ● Aug. 11, 2026

This was a Thursday, and Toby assumed this meant he would see the boy one more time, on Friday after school.

From "Not Nothing" by Gayle Forman

But it offers a warning against assuming that a small fee will have a small effect.

From BBC ● Aug. 16, 2026

"The results at some were literally off the scale and will have a big impact in professional circles, assuming they cannot continue to try to ignore them now," he said.

From BBC ● Aug. 15, 2026

I’m assuming neither do you, and neither does anyone posting about it.

From The Wall Street Journal ● Aug. 7, 2026

Heirs receive assets after valid claims are resolved, assuming that probate assets actually exist.

From MarketWatch ● Aug. 6, 2026

I’ll just say Ethan’s the reason I spent years assuming all straight guys were into musicals.

From "What If It's Us" by Becky Albertalli and Adam Silvera

Related Words

• accept
• conclude
• consider
• estimate
• expect
• guess
• infer
• presume
• speculate
• suspect
• think
• understand