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English definition of “addition”

addition

noun  /əˈdɪʃ·ən/ us  

addition noun (CALCULATION)

mathematics [U] the process of calculating the total of a group of numbers: [U] We learn addition and subtraction in first and second grade.

addition noun (INCREASE)

[C/U] the joining of something to something else to make it larger or more important, or the person or thing that joins something: [C] Harold is the newest addition to our staff.
(Definition of addition from the Cambridge Academic Content Dictionary © Cambridge University Press)
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