ad·​di·​tion | \ ə-ˈdi-shən How to pronounce addition (audio) , a-\

Definition of addition

1 : a part added (as to a building or residential section) The addition expanded the kitchen.
2 : anything or anyone added : increase The clerk was a recent addition to the staff.
3 : the act or process of adding a recipe enhanced by the addition of freshly ground pepper especially : the operation of combining numbers so as to obtain an equivalent simple quantity schoolchildren learning about addition and subtraction
4 : direct chemical combination of substances into a single product
in addition
: besides entry 2, also The job requires a college degree and, in addition, at least two years of experience.
in addition to
: combined or associated with : besides entry 1 sense 2 In addition to soup, several salads were served.

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Synonyms for addition


annex, extension, penthouse

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Examples of addition in a Sentence

The children learned addition and subtraction. The museum's collection includes several new additions.

Recent Examples on the Web

In addition to the presidential vote, previously delayed parliamentary elections are scheduled to be held in embattled Ghazni province. Washington Post, "Taliban threatens to disrupt Afghan elections, dismisses September polls as ‘ploy’," 6 Aug. 2019 In addition to long term human damage causing the decline, a natural rock slide also is imperiling the Fraser River salmon. Anchorage Daily News, "Where are the salmon and the orcas? Tribe, scientists grapple with unprecedented disappearance in Washington waters," 6 Aug. 2019 The Texas shooter, who might have been motivated by white nationalist and racist views, may face hate crime charges in addition to capital murder charges. Lisa J. Huriash,, "Parkland students demand presidential candidates ‘have a plan’," 6 Aug. 2019 In addition to the leaf survey, the volunteer side of the project involves counting stomatal pores captured in images of modern and fossilized leaves. Meilan Solly, Smithsonian, "Smithsonian Scientists Need Ginkgo Leaves to Study Climate Change—They Need Your Help," 6 Aug. 2019 In addition to the modern Class-A office space, Ribbon is building out a state-of-the-art R&D lab and customer support center, through which multiple products and solutions are developed and supported. Steve Brown, Dallas News, "Plano business campus lands huge tech firm tenant," 6 Aug. 2019 In addition to the trade war with China, other factors are at work. Erik Sherman, Fortune, "Dow, S&P 500, Nasdaq Plunge Some 3% on Renewed Trade War Fears," 5 Aug. 2019 In addition to editing and writing stories for the now-quarterly magazine in its 35th year of publication by the city, O'Connor was credited bringing in a professional advertising manager. Thomas Jewell,, "Julie McGovern Voyzey takes over helm in Shaker Communications & Marketing," 5 Aug. 2019 As an accomplished, unapologetic and, yes, demanding woman artist, Czeresko must confront sexist reality TV tropes in addition to art world misogyny., "‘Blown Away’ star says she ‘expected there to be a backlash’," 5 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'addition.' 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 addition

14th century, in the meaning defined at sense 1

History and Etymology for addition

Middle English addicioun, borrowed from Anglo-French addicion, borrowed from Latin additiōn-, additiō, from addi-, variant stem of addere "to add" + -tiōn-, -tiō, suffix of action nouns

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Statistics for addition

Last Updated

9 Aug 2019

Look-up Popularity

Time Traveler for addition

The first known use of addition was in the 14th century

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More Definitions for addition



English Language Learners Definition of addition

: the act or process of joining something to something else : the act or process of adding something
mathematics : the act or process of adding numbers
: something or someone more that is included : something or someone that is added


ad·​di·​tion | \ ə-ˈdi-shən How to pronounce addition (audio) \

Kids Definition of addition

1 : the act or process of adding numbers to obtain their sum
2 : something added an addition to a house
in addition
: as something more
in addition to
: along with or together with There was ice cream in addition to cake and pie.

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Comments on addition

What made you want to look up addition? Please tell us where you read or heard it (including the quote, if possible).


a period when something is suspended

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