addition (additions plural )
1 You use in addition when you want to mention another item connected with the subject you are discussing.
♦
in addition phrase PHR with cl, oft PHR to n
Part-time English classes are offered. In addition, students can take classes in word-processing and computing..., There's a postage and packing fee in addition to the repair charge.
2 n-count An addition to something is a thing which is added to it.
usu with supp, oft N to n
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.
the N of n (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.