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


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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 While stirring, add the water in thirds, letting each addition incorporate before adding the next. cleveland, "Your next quarantine cooking project: Homemade noodles," 27 May 2020 The seeds are then synced among all the devices such that a change or addition on one device will automatically be populated to all the others. Dan Goodin, Ars Technica, "Choosing 2FA authenticator apps can be hard. Ars did it so you don’t have to," 27 May 2020 With the eligibility of Wake Forest transfer Olivier Sarr uncertain for next season, Kentucky could use another frontcourt addition, but much of the buzz in Cisse's recruitment has centered on other programs of late. Jon Hale, The Courier-Journal, "Kentucky basketball recruiting target Moussa Cisse reclassifying to 2020," 27 May 2020 That freedom to fumble their way through their teen years is what makes these girls such vibrant and necessary additions to the coming-of-age canon. Hannah Giorgis, The Atlantic, "The Secret Lives of Teenage Sidekicks," 26 May 2020 In addition to flooding, a low end tornado risk exists as well, especially across eastern North Carolina and South Carolina. NBC News, "Tropical Storm Bertha makes landfall near Charleston, South Carolina," 26 May 2020 One new addition to Sottile’s will be Wisconsin microbrews. Erik S. Hanley, Milwaukee Journal Sentinel, "A Cudahy pub with a secret floor and a long possibly haunted history was remodeled during the coronavirus quarantine," 26 May 2020 In the past several weeks, Millennium announced two high-profile additions. Katherine Burton,, "Hedge Funds Pay Up in U.S. to Poach From Rivals Stung by Turmoil," 26 May 2020 Nouns can change once, and then change forever, all thanks to a small addition. Hilary Leichter, Harper's Magazine, "Terrace Story," 25 May 2020

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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Time Traveler for addition

Time Traveler

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

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Statistics for addition

Last Updated

30 May 2020

Cite this Entry

“Addition.” Dictionary, Merriam-Webster, Accessed 5 Jun. 2020.

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How to pronounce addition (audio)

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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