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, the strip of winter storm and blizzard warnings stretching from South Texas to Jacksonville, Fla. is something rarely seen, as a low pressure area traverses the central Gulf of Mexico, directing abundant moisture northward, into the frigid air mass. —Andrew Freedman, Axios, 22 Jan. 2025

In addition, the company’s earnings per share came in at $1.51, up 39% y-o-y. —Trefis Team, Forbes, 21 Jan. 2025

In addition, the executive order calls for the attorney general to block the use of federal funding for medical treatment or procedures for gender transition for prisoners. —Emily Alpert Reyes, Los Angeles Times, 21 Jan. 2025

In addition, the order directs the Interior Department to halt the construction of a wind farm in Idaho that was approved under the Biden administration. —Rachel Frazin, The Hill, 21 Jan. 2025

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)