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 In addition, measurement must also be a core component of talent processes. Jennifer Garrard, Forbes, "The Three Pillars Of Engaging Organizational Talent," 6 May 2021 In addition, investigators found items in the bar allegedly used to distribute the fake cards. Aya Elamroussi, CNN, "California bar owner charged with multiple felonies for allegedly selling fake Covid-19 vaccination cards, officials say," 6 May 2021 In addition, there are 41 confirmed and two probable cases of the B.1.351 strain first detected in South Africa. Nushrat Rahman, Detroit Free Press, "Michigan reports 3,514 new COVID-19 cases, 115 deaths, 40% of people 16+ fully vaccinated," 6 May 2021 In addition, at a time in which learning is an increasingly collaborative process that requires a range of flexible spaces for gatherings and research, the additions contained load-bearing stacks that could neither be moved nor rearranged. Los Angeles Times, "How a pandemic year of loss reshaped Maya Lin’s art and architecture," 6 May 2021 In addition, some states have resisted existing federal preschool grants, objecting to federal control or other issues. USA TODAY, "Exclusive: Biden looking to sell child care, education plan with state-specific pitches," 6 May 2021 In addition, Middleton garnered the Arizona Interscholastic association's Conference 6A Player of the Year after last season. Dana Scott, The Arizona Republic, "Hamilton's Jordan Middleton named 2020-21 Gatorade Arizona Volleyball Player of the Year," 6 May 2021 In addition, 89% of all high school applicants were matched with one of their top three choices of selective enrollment schools, an increase of around 9 percentage points from 2020, and 95% of those who applied received an offer, according to CPS. Karen Ann Cullotta,, "CPS selective enrollment high schools will nearly double the number of diverse learners next year," 6 May 2021 In addition, the federal government is the source for the state’s four Federal Emergency Management Agency sites set up for mass-vaccination in Orlando, Tampa, Jacksonville and Miami. Richard Tribou,, "Florida COVID vaccine supply remains near 600k doses for next week," 6 May 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

9 May 2021

Cite this Entry

“Addition.” Dictionary, Merriam-Webster, Accessed 15 May. 2021.

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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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