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 Young astronauts have a new forum to discover planets and delve into galaxies at Planet Play, the latest addition to the Kennedy Space Center Visitor Complex. Star Tribune, "Airlines, including Delta, have banned emotional support animals; cruises canceled into spring," 15 Jan. 2021 Complete with a nonstick cooking surface, this gadget make the cooking—and cleaning—process relatively speedy, providing the perfect addition to your breakfast routine. Melissa Lee, USA TODAY, "The 5 best Amazon deals you can get this Thursday," 15 Jan. 2021 While the veteran seems to be most likely to get squeezed by the Allen addition, the rash of injuries throughout the first few weeks makes depth an asset. Chris Fedor, cleveland, "Cleveland Cavaliers jump in James Harden trade, steal Jarrett Allen and make big addition to growing young core," 14 Jan. 2021 In addition to spur-of-the-moment travel, spring bookings are ramping up. Rosemary Mcclure, Los Angeles Times, "Travel with your ‘pod’ on a private hiking or biking tour," 14 Jan. 2021 There are more than 217,000 residents age 65 and older eligible for the vaccine in Oakland County, in addition to frontline essential workers, according to the release. Christina Hall, Detroit Free Press, "Oakland Co. launches link to help ID those eligible, interested in COVID-19 vaccine," 14 Jan. 2021 In fact, even SVU's own leading lady Mariska Hargitay (a.k.a. Olivia Benson) had something to say about the furry addition to the show's set back in 2015. Hannah Jeon, Good Housekeeping, "An Eagle-Eyed 'Law and Order: SVU' Fan Caught Something Very Interesting on Amanda’s Desk," 14 Jan. 2021 But $50 billion in grants and loans from the federal government and the ability to borrow money -- and in some cases sell addition shares of stock -- has left US airlines with enough cash. Chris Isidore, CNN, "Delta turned record profit into a record loss in one year," 14 Jan. 2021 In addition to the violence last week, there have been reports of threats of violence leading up to Biden's inauguration on Jan. 20. Mike Brest, Washington Examiner, "Troops nap in Capitol ahead of preparations for Biden inauguration," 13 Jan. 2021

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

21 Jan 2021

Cite this Entry

“Addition.” Dictionary, Merriam-Webster, Accessed 26 Jan. 2021.

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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

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