addition

noun

ad·​di·​tion ə-ˈdi-shən How to pronounce addition (audio)
a-
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.
New additions include Somni in West Hollywood, Addison by William Bradley in San Diego, and Sons and Daughters in San Francisco. Angela Osorio, Los Angeles Times, 30 May 2026 That being said, Breslow confirmed that the Red Sox have explored making external additions to help the team. Mac Cerullo, Boston Herald, 30 May 2026 In addition to queen rooms, there is also a family suite option with a private King room, bunk beds and a queen-sized pull-out with a kitchenette. Ella Gonzales may 29, Fort Worth Star-Telegram, 29 May 2026 In addition to selling precious metal products, the brand also buys gold from consumers and offers a gold IRA. Liz Knueven, CNBC, 29 May 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 31 May. 2026.

Kids Definition

addition

noun
ad·​di·​tion ə-ˈdish-ən How to pronounce addition (audio)
a-
1
: the result of adding : increase
2
: the act, process, or operation of adding
3
: a part added (as to a building)

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