ad·di·tion | \ə-ˈdi-shən, 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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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

West Ham have already bolstered their midfield with the £17.5m addition of Borussia Dortmund winger Andriy Yarmolenko this week, having already signed Jack Wilshere, Issa Diop, Lukasz Fabianski and Ryan Fredericks this summer., "Lazio Star Felipe Anderson Undergoing West Ham Medical as Club Record Move Edges Closer," 13 July 2018 Proponents of a larger event point to the addition of teams that otherwise would have failed to qualify in a smaller field. Steven Goff,, "FIFA president: World Cup could expand to 48 teams in 2022, ahead of schedule," 13 July 2018 BMG CEO Hartwig Masuch announced today in Berlin the addition of a pair of top executives in his head office. Wolfgang Spahr, Billboard, "BMG Promotes Ben Katovsky to COO, Ama Walton to Global General Counsel," 13 July 2018 Media: Euronews Proponents of a larger event point to the addition of teams that otherwise would have failed to qualify in a smaller field. Steven Goff, Houston Chronicle, "FIFA president: World Cup could expand to 48 teams in 2022, ahead of schedule," 13 July 2018 The addition of a quarter of an avocado to a full portion would bring this meal to 397 calories, 18 grams of fat, 34 grams of carb with 8 as fiber, and 30 grams of protein., "The 4 Healthiest Menu Items at Panera Bread (Plus 3 Things to Avoid)," 13 July 2018 Summer campers at the Galbut Family Miami Beach Jewish Community Center's Camp Klurman enjoyed the addition of a drone flying specialty camp. Sergio Carmona, Jewish Journal, "Drone camp added to programming at Miami Beach JCC," 13 July 2018 The addition of Lewis will only help keep the former Heisman winner fresh and healthy. Eddie Brown,, "Fantasy Football 2018: Tennessee Titans Preview," 13 July 2018 The International Olympic Committee created a new policy in their 2014 strategic roadmap that would allow for the addition of five new sports for each games, without replacing existing Olympic sports. Madeline Mitchell,, "Ultimate Frisbee is likely to fly into the 2024 or 2028 Olympic Games. You can see the world's top players here in Greater Cincinnati," 12 July 2018

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

4 Oct 2018

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 \

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

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