sum·​ma·​tion | \(ˌ)sə-ˈmā-shən \

Definition of summation 

1 : the act or process of forming a sum : addition

2 : sum, total

3 : cumulative action or effect especially : the process by which a sequence of stimuli that are individually inadequate to produce a response are cumulatively able to induce a nerve impulse

4 : a final part of an argument reviewing points made and expressing conclusions

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Other Words from summation

summational \(ˌ)sə-​ˈmā-​shnəl, -​shə-​nᵊl \ adjective

Examples of summation in a Sentence

A summation can be found at the end of the report. We gave a summation of our discovery. The defense attorneys and prosecutors are set to make their final summations today.
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Recent Examples on the Web

His attorneys, in their own summations, told the jury that the government had failed to present enough evidence to prove the charges beyond a reasonable doubt. Aruna Viswanatha, WSJ, "Manafort Jury Ends First Day of Deliberations," 16 Aug. 2018 Dean is a master of the art of summation, briskly anchoring readers who may be unfamiliar with these writers before moving on to make connections between them. Meg Waite Clayton, San Francisco Chronicle, "‘Sharp: The Women Who Made an Art of Having an Opinion,’ by Michelle Dean," 23 May 2018 The game was a summation of Mathias’ four years at Purdue. Gregg Doyel, Indianapolis Star, "Doyel: Purdue's seniors changed everything and still didn't get a nickname," 25 Feb. 2018 Together the messages are the perfect summation of all that the Knotty Pine is. Devra First,, "Why the club sandwich may just be the perfect American food," 11 June 2018 Yet there Miranda was, staring at the camera and giving a completely honest summation of her greatest romantic worry., "Sex And The City Might Be Dated, But It’ll Never Get Old," 6 June 2018 On a wall of her room back in Grants Pass, Deshae has slapped up a slew of Post-It notes, and written on a red one next to a cup of pens—amidst the Bible verses and reminders to herself—is a simple summation of her life so far. Jeremy Fuchs,, "Life After Escaping the World of Human Trafficking," 10 May 2018 When the alternates were released, after summations, three stayed to wait for a verdict. Maureen O'connor, The Cut, "The Jury and the Family Speak Out As the Nanny Trial Ends," 19 Apr. 2018 Now, on the eve of the film's release, he's found himself in a strange place: First Reformed feels like a career summation, the period at the end of a sentence. Zach Baron, GQ, "Paul Schrader Isn't Done Yet," 18 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'summation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of summation

1760, in the meaning defined at sense 1

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Statistics for summation

Last Updated

21 Nov 2018

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Time Traveler for summation

The first known use of summation was in 1760

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More Definitions for summation



English Language Learners Definition of summation

: a brief description of the most important information about something

law : a final speech made by a lawyer in a court of law to give a summary of the main arguments in a case


sum·​ma·​tion | \(ˌ)sə-ˈmā-shən \

Medical Definition of summation 

: cumulative action or effect especially : the process by which a sequence of stimuli that are individually inadequate to produce a response are cumulatively able to induce a nerve impulse — see spatial summation, temporal summation


sum·​ma·​tion | \sə-ˈmā-shən \

Legal Definition of summation 

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More from Merriam-Webster on summation

Rhyming Dictionary: Words that rhyme with summation

Thesaurus: All synonyms and antonyms for summation

Spanish Central: Translation of summation Encyclopedia article about summation

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