Jump To:

• sum
  sum

  noun

  the aggregate of two or more numbers, magnitudes, quantities, or particulars as determined by or as if by the mathematical process of addition.
• SUM
  SUM

  surface-to-underwater missile.
• sum-
  sum-

  variant of sub- before m: summon.

sum

¹ American  

[suhm] / sʌm /

noun

• sums
  plural

1. the aggregate of two or more numbers, magnitudes, quantities, or particulars as determined by or as if by the mathematical process of addition.

   The sum of 6 and 8 is 14.

2. a particular aggregate or total, especially with reference to money.

   The expenses came to an enormous sum.

3. an indefinite amount or quantity, especially of money.

   to lend small sums.

4. a series of numbers or quantities to be added up.

5. an arithmetical problem to be solved, or such a problem worked out and having the various steps shown.

6. the full amount, or the whole.

7. the substance or gist of a matter, comprehensively or broadly viewed or expressed.

   the sum of his opinions.

8. concise or brief form.

   in sum.

9. Mathematics.

   1. the limit of the sequence of partial sums of a given infinite series.

   2. union.

10. a summary.

---

verb (used with object)

• sums,
  present (3rd person singular)
• summed,
  past participle,  past
• summing
  present participle

1. to combine into an aggregate or total (often followed byup ).

2. to ascertain the sum of, as by addition.

3. to bring into or contain in a small compass (often followed byup ).

verb (used without object)

• sums,
  present (3rd person singular)
• summed,
  past participle,  past
• summing
  present participle

1. to amount (usually followed by to orinto ).

   Their expenses summed into the thousands.

verb phrase

1. sum up

   1. to reckon.

      We summed up our assets and liabilities.

   2. to bring into or contain in a brief and comprehensive statement; summarize.

      to sum up the case for the prosecution.

   3. to form a quick estimate of.

      I summed him up in a minute.

SUM ² American  

1. surface-to-underwater missile.

---

sum- ³ American  

1. variant of sub- before m: summon.

---

sum ¹ British  

/ sʌm /

noun

1. 1. the result of the addition of numbers, quantities, objects, etc

   2. the cardinality of the union of disjoint sets whose cardinalities are the given numbers

2. one or more columns or rows of numbers to be added, subtracted, multiplied, or divided

3. maths the limit of a series of sums of the first n terms of a converging infinite series as n tends to infinity

4. (plural) another name for number work

5. a quantity, esp of money

   he borrows enormous sums

6. the essence or gist of a matter (esp in the phrases in sum, in sum and substance )

7. a less common word for summary

8. archaic the summit or maximum

9. (modifier) complete or final (esp in the phrase sum total )

---

verb

1. (often foll by up) to add or form a total of (something)

2. (tr) to calculate the sum of (the terms in a sequence)

sum ² British  

/ sʊm /

noun

1. the standard monetary unit of Uzbekistan, divided into 100 tiyin

---

sum Scientific  

/ sŭm /

1. The result of adding numbers or quantities. The sum of 6 and 9, for example, is 15, and the sum of 4 x and 5 x is 9 x.

---

Synonym Usage

See number.

Other Word Forms

Derived Forms

• sumlessness
  noun
• outsum
  verb (used with object)
• sumless
  adjective

Inflected Forms

Nouns

• sums
  plural

Participles

• summing
  present
• summed
  past

Conjugated Forms

Present

• sum
  simple
• sums
  simple
• have summed
  perfect
• has summed
  perfect
• am summing
  progressive
• are summing
  progressive
• is summing
  progressive
• have been summing
  perfect progressive
• has been summing
  perfect progressive

Past

• summed
  simple
• had summed
  perfect
• was summing
  progressive
• were summing
  progressive
• had been summing
  perfect progressive

Future

• will sum
  simple
• will have summed
  perfect
• will be summing
  progressive
• will have been summing
  perfect progressive

Etymology

Origin of sum

First recorded in 1250–1300; (noun) Middle English summe, from Latin summa “sum,” noun use of feminine of summus “highest,” superlative of superus ( see superior); (verb) Middle English summen (from Old French summer ), from Medieval Latin summāre, derivative of summa

Explanation

When you determine the sum, you add up all the numbers. When you sum something up, you focus on all of its important points. The word sum can also refer to a certain amount of money. A new car might cost you a huge sum of money. But if you sum or add up all its benefits, you might be able to justify spending so much. You calculate the total on a restaurant bill when you sum up the prices of everything you ordered. Sum doesn't have to refer strictly to numbers. When you sum something up, you're giving an overview or general statement about it.

Example Sentences

See Examples For:

sum SUM sum- sums summed summing

There’s a hidden benefit to spending a vast sum of money to buy a pro sports team.

From Barron's ● Aug. 22, 2026

In July, the two parties settled the suit for an undisclosed sum.

From Salon ● Aug. 20, 2026

The goal with an annuity is to put down a lump sum today that will give you a payout for the fixed costs you want to cover for your lifetime.

From MarketWatch ● Aug. 19, 2026

For the most part, the sum reflected Romney’s earnings from Bain Capital, the private-equity firm he co-founded.

From Los Angeles Times ● Aug. 14, 2026

Once again, let us consider the story of Achilles and the tortoise, which is an infinite sum of steps that get closer and closer to zero.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

SUM has staged 100 games for Mexico’s men’s team in the U.S. over the last 20 years, annual tours that account for more than a third of the federation’s annual budget.

From Los Angeles Times ● Jun. 27, 2022

SUM profits when Mexico’s national team is promoted in the US.

From The Guardian ● Jan. 19, 2018

A healthy slice of the revenue from those events and from sponsorship deals cut by SUM is distributed to the owners of MLS teams.

From Washington Post ● Jun. 17, 2016

The organizers capitalized SUM at the exorbitant amount of $500,000 and named the nation’s first planned industrial city in honor of New Jersey governor William Paterson.

From Time ● Dec. 28, 2015

The Greek form of the same verb was ESMI, which became ASMI, and in Latin the first and last vowels have disappeared, the verb is SUM.

From Bulfinch's Mythology: the Age of Fable by Thomas Bulfinch

He was embarrassed at having sum- moned a senior representative of the U.S. government all this way.

From MSNBC ● Nov. 7, 2017

The company is worth at least $72 a share, based on a sum- of-the-parts analysis by Bernstein’s Dibadj.

From BusinessWeek ● Sep. 21, 2011

“Is it true that on sundry occasions during the sum- mer you have entered her house and visited with her?”

From "The Witch of Blackbird Pond" by Elizabeth George Speare

By sum- mer he’d learned the basics of the uranium bomb.

From "Bomb" by Steve Sheinkin

He did not have the careless, almost British look of most of the Devon Masters, because he was a substitute for the sum- mer.

From "A Separate Peace" by John Knowles

In cash-flow terms, he notes, many of the biggest tech companies are now cash flow negative as they spend gigantic sums of money on new AI data centers.

From MarketWatch ● Aug. 20, 2026

The sums are vast, but the explanations for the spending range from vague to inscrutable.

From Salon ● Aug. 20, 2026

For clubs accustomed to paying tens of millions for established first-team players, spreading comparatively modest sums across several promising teenagers offers obvious appeal.

From BBC ● Aug. 15, 2026

Governments and tech giants are pouring huge sums into building data centres that can train and run AI tools such as chatbots, image generators and agents that can execute tasks.

From Barron's ● Aug. 12, 2026

Celebrities had been known to pay huge sums of money to buy an avatar name they wanted from a cyber-squatter who had already reserved it.

From "Ready Player One: A Novel" by Ernest Cline

Meta's business model could be summed up this way: "Hook the users; hold them for as long as they can; harvest their data; hide the truth from the public when making public statements," she said.

From BBC ● Aug. 18, 2026

Alex Vatanka, another senior fellow from the Middle East Institute, summed up the situation, describing it as a "lose-lose equation" in which "neither side is benefiting."

From Barron's ● Jul. 31, 2026

Thill, the Jefferies analyst, summed up the Meta call.

From The Wall Street Journal ● Jul. 30, 2026

B. Riley analyst Mike Crawford summed up the political-military scene in a note to clients on Thursday by referring to “an emerging generational recapitalization of global defense posture and budgets.”

From MarketWatch ● Jul. 23, 2026

The change could be summed up simply: before, they had been employees; now they were followers.

From "Educated" by Tara Westover

Mike Murphy continues his wonderful series of What’s Worth Streaming, reviewing the offerings from eight streaming services and summing up which ones are worth paying for and which ones you should skip for the month.

From MarketWatch ● Jul. 2, 2026

The inquest began at the end of January, and the coroner Mr Justice Rooney completed his summing up on Monday.

From BBC ● Jun. 30, 2026

In summing up his aspirations, Angle mentions the film “Jurassic Park.”

From The Wall Street Journal ● May 4, 2026

Duterte's defence lawyer Nicholas Kaufman, summing up his case, said that if his client could be faulted for anything, it was his "inappropriate choice of language".

From Barron's ● Feb. 27, 2026

That,” said Joe, summing up with his judicial air, “were the word of Biddy. ‘Go to him,’ Biddy say, ‘without loss of time.’

From "Great Expectations" by Charles Dickens

Related Words

• amount
• bulk
• quantity
• value
• worth