The definition of addition is the process of bringing two or more numbers or things together.(noun)
Calculating the sum of 25 and 60 is an example of addition.
See addition in Webster's New World College Dictionary
Origin: ME addicion < OFr addition < L additio < addere: see add
See addition in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Latin additiō, additiōn-
Origin: , from additus
Origin: , past participle of addere, to add; see add.
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