addition

noun ad·di·tion \ ə-ˈdi-shən , a- \
Updated on: 15 Nov 2017

Definition of addition

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
in addition
:2besides, also
  • The job requires a college degree and, in addition, at least two years of experience.
in addition to
:combined or associated with :1besides 2
  • In addition to soup, several salads were served.

Examples of addition in a Sentence

  1. The children learned addition and subtraction.

  2. The museum's collection includes several new additions.

Recent Examples of addition from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'addition.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of addition

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

Other Building Terms


ADDITION Defined for English Language Learners

addition

noun

Definition of addition for English Language Learners

  • : the act or process of joining something to something else : the act or process of adding something

  • mathematics : the act or process of adding numbers

  • : something or someone more that is included : something or someone that is added


ADDITION Defined for Kids

addition

noun ad·di·tion \ ə-ˈdi-shən \

Definition of addition for Students

1 :the act or process of adding numbers to obtain their sum
2 :something added
  • an addition to a house
in addition
:as something more
in addition to
:along with or together with
  • There was ice cream in addition to cake and pie.


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