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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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 Greenland’s ice sheet, parts of the Antarctic ice sheet are melting as well. Umair Irfan, Vox, "Greenland’s ice sheet is melting at its fastest rate in centuries," 8 Dec. 2018 In the Oosterhouse home, these are a key part of the decor, in addition to her beloved ceramic houses and white string lights, of course. Taylor Mead, House Beautiful, "Actress Amy Smart Reveals How She Decorates Her Home For The Holidays With Husband Carter Oosterhouse," 7 Dec. 2018 In addition to Kendrick's eight nominations and Drake's seven nominations, artists including Childish Gambino, Mac Miller, Chloe x Halle, and Janelle Monae are also up for awards. Lauren Rearick, Teen Vogue, "Grammys 2019 Nominations Include Multiple Nods for Ariana Grande and Dua Lipa," 7 Dec. 2018 While chewing gum will stimulate more salivary flow and help prevent tooth decay in addition to freshening you up, sometimes the situation calls for something a little more discreet. Caroline Picard, Good Housekeeping, "The 8 Best Breath Mints to Carry Around With You All Day," 7 Dec. 2018 In addition to Williams, Forbes also named women like Shonda Rimes, Oprah, and Beyoncé as the world's most powerful, and German chancellor Angela Merkel holds the number one spot for the eighth year in a row. Julyssa Lopez, Glamour, "Serena Williams Makes Forbes' Most Powerful Women List for the First Time," 7 Dec. 2018 In addition to building and selling all types of ramps, Keen spends an enormous amount of time and energy helping the local skate community. Timothy Dahl, Popular Mechanics, "Big Air For a Higher Purpose," 6 Dec. 2018 In addition to speeds, the Measuring Broadband America reports also include data on latency and packet loss. Jon Brodkin, Ars Technica, "Ajit Pai buries 2-year-old speed test data in appendix of 762-page report," 5 Dec. 2018 In addition to his work overseas, Chris is also passionate about his hometown of Barron, Wisconsin. Alisa Wolfson, Country Living, "'The Voice' Star Chris Kroeze on the Heartbreaking Reason He May Stop Singing Overseas," 4 Dec. 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

13 Dec 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

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


a soft lustrous wool fabric with mohair

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