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 Marlow is charged with three counts of drug trafficking, importing heroin, possession of marijuana and possession of drug paraphernalia in addition to her child support warrant and misdemeanor theft warrant, according to court records. Madeline Mitchell,, "More than $36,000 worth of heroin, cocaine, meth and marijuana seized in single traffic stop," 8 Jan. 2020 In addition to Freed, of Manhattan, survivors include her mother, of Manhattan and Fort Lauderdale. Harrison Smith, Anchorage Daily News, "Elizabeth Wurtzel, ‘Prozac Nation’ author who spurred a memoir boom, dies at 52," 8 Jan. 2020 In addition to requiring a photo ID at polling stations, voters would now have to provide a photo ID to vote absentee by mail under the bill. Joe Sonka, The Courier-Journal, "Kentucky Republicans say voter ID bill will 'increase confidence' in election process," 8 Jan. 2020 In addition to Sonnett and Foord, the Thorns sent the Nos. 7 and 14 picks in the Jan. 16 draft to the Pride in exchange for the No. 1 pick. oregonlive, "Portland Thorns acquire No. 1 overall pick in NWSL draft in trade with Orlando Pride," 8 Jan. 2020 TikTok hasn’t made any additional announcements about changes to moderation staffing or other enforcement mechanisms in addition to its new Community Guidelines. Louise Matsakis, Wired, "New Rules, Who Dis: TikTok Overhauls Its Community Guidelines," 8 Jan. 2020 In addition to overseeing their respective special education programs, Rood and Roberts will split the administrative duties that previously fell to the director role. Mj Slaby, Indianapolis Star, "After removing director over offensive meme, Noblesville has new special education leaders," 8 Jan. 2020 Building a 1,500-mile long permanent barrier across one of the most sensitive landscapes in America, in addition to the impact on humans, could split breeding animal populations in half. Jordan G. Teicher, The New Republic, "An Animal’s-Eye View of Mass Extinction in Progress," 7 Jan. 2020 In addition to having more early voting sites than in past primaries, the county’s new voting system will allow voters to cast ballots at any of the roughly 280 polling sites countywide on Election Day. Scott Huddleston,, "Early vote sites for San Antonio area approved for March 3 primaries," 7 Jan. 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

11 Jan 2020

Cite this Entry

“Addition.” The Dictionary, Merriam-Webster Inc., Accessed 20 January 2020.

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More Definitions for addition


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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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).


not to be intimidated or subdued

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