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, ensure that any business contracts, documents, files, etc. Tom Cooney And Crystal Faulkner,, "Businesswise: Pay attention to business value drivers before an exit looms," 10 June 2019 But the addition of the Raptors and the Grizzlies — the first time the NBA had expanded since the late 1980s — was intended to help boost the NBA’s image (not to mention inject a healthy financial infusion of $125 million per franchise). Matt Giles, Longreads, "How the Toronto Raptors and the Vancouver Grizzlies Revived the NBA," 8 June 2019 This year, the historic perch had a new addition: Prince Louis. Vogue, "See Prince Louis’s Adorable Trooping the Colour Debut," 8 June 2019 In addition, all of his PAT passes were caught, making his night even more noteworthy. Robert Avery, Houston Chronicle, "Furr QB throws 5 TD passes as Brahmas down Deer Park in opening 7-on-7 action," 7 June 2019 Armor - Fumi Nikaido A relatively recent addition to the X-Men mythos, the Japanese mutant, Hisako Ichiki, has the power to create a psychic exoskeleton that gives her super-strength and invulnerability. Richard Newby, The Hollywood Reporter, "Who Can Play the X-Men Now?," 7 June 2019 The collection of video evidence is a new addition, which would require police to attempt to obtain and review any and all recordings of incidents where force is used. Talis Shelbourne, Milwaukee Journal Sentinel, "New use-of-force policies aim to change first aid treatment, handling of suicidal civilians and more," 6 June 2019 There weren’t any additions to the injury report, although safety Blake Countess wasn’t in attendance for an unknown reason. Jeff Mclane,, "Eagles Practice Observations: J.J. Arcega-Whiteside shines in the red zone; Sidney Jones caps solid OTAs with an INT; Malik Jackson arrives," 5 June 2019 The additions, approved by the state consumer protection commissioner on Monday, will push the list to 44 total conditions for which Connecticut patients could qualify for the use of medical marijuana. Zach Murdock,, "State physicians recommend 5 new conditions for medical marijuana program, delay decision on addition of chronic pain," 5 June 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

14 Jun 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).


showing courage and determination

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