addition

noun

ad·​di·​tion ə-ˈdi-shən 

a-

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

Phrases

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.

Synonyms

• annex
• extension
• penthouse

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 this, Smith celebrated 17 top-five finishes, leading numerous laps across various tracks. —Gord Magill, Newsweek, 22 Dec. 2024

The appointee will be essential in carrying out Trump’s aggressive immigration plans, in addition to the agency’s duties surrounding cybersecurity, antiterrorism and emergency response. —Sara Dorn, Forbes, 22 Dec. 2024

In addition to how the vehicle is moving, information about fuel consumption, brake wear, and tire temperature is shared with the team. —Roberto Baldwin, Ars Technica, 22 Dec. 2024

Editors’ Picks The Fair Catch Free Kick, and 4 Other Obscure-but-Real N.F.L. Rules Some institutions, such as New York University, agreed to make payments in addition to reviewing policies to settle legal claims. —Orlando Mayorquín, New York Times, 22 Dec. 2024

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

Kids Definition

addition

noun

ad·​di·​tion ə-ˈdish-ən 

a-

1

: the result of adding : increase

2

: the act, process, or operation of adding

3

: a part added (as to a building)