addition (additions plural )
1 You use in addition when you want to mention another item connected with the subject you are discussing.
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in addition phrase
Part-time English classes are offered. In addition, students can take classes in word-processing and computing...
2 n-count An addition to something is a thing which is added to it.
This is a fine book; a worthy addition to the Cambridge Encyclopedia series...
3 n-uncount The addition of something is the fact that it is added to something else., (Antonym: removal)
It was completely refurbished in 1987, with the addition of a picnic site.
4 n-uncount Addition is the process of calculating the total of two or more numbers.
...simple addition and subtraction problems.