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

Santoro said in addition to Los Angeles-Long Beach delays, vessel diversions to U.S. West coast ports could cause congestion to spike and prompt cargo processing backlogs at additional ports such as Seattle and Oakland. —Lori Ann Larocco, CNBC, 4 Nov. 2024

The addition adds contrast for form-fitting looks and elevates designer threads — like Comer’s Prada jumpsuit at her most recent red carpet event. —Julia Teti, WWD, 4 Nov. 2024

The addition of Dolgin to the team is the first new hire at AMG under CEO Elliot Grainge. —Thania Garcia, Variety, 4 Nov. 2024

In addition to helping his campaign, Trump’s donors have also helped to finance his personal legal bills through his leadership PAC Save America, which has been used to pay his legal fees as cases against him have piled up. —Alison Durkee, Forbes, 4 Nov. 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)