Synonyms of additionnext
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

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Multiple states now restrict forever chemicals, with Minnesota last year banning the intentional addition of PFAS to 11 categories of consumer products, including dental floss. — Margaret Hetherman The Washington Post, Arkansas Online, 19 Oct. 2026 Museum will add new west wing The Nelson-Atkins Museum of Art is planning a major expansion to the west, highlighted by a two-level glass addition topped with a green roof. — Neil Nakahodo, Kansas City Star, 18 Oct. 2026 Even a more recent addition such as the Leonard Louis Fieldhouse in Chinatown’s Ping Tom Park (2013, Wright & Company) seems dropped into its riverfront location from a suburban warehouse district. — Edward Keegan, Chicago Tribune, 18 Oct. 2026 The new Minhwa Spirits tasting room will take over the former Aziza space in the Westside Provisions District development on Howell Mill Road, a major addition to the development. — Henri Hollis, AJC.com, 17 Oct. 2026 See All Example Sentences for addition

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of addition was in the 14th century

Browse Nearby Words

Cite this Entry

“Addition.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/addition. Accessed 20 Oct. 2026.

Kids Definition

addition

noun
1
: the result of adding : increase
2
: the act, process, or operation of adding
3
: a part added (as to a building)

More from Merriam-Webster on addition

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!