addition · noun /əˈdɪʃ.ən/Full view
Nouns: addition
Adjectives: additional
Verbs: add
Adverbs: additionally
in addition (to)
B1 as well (as)
Dictionary example:

In addition to his flat in London, he has a villa in Italy and a castle in Scotland.

Learner example:

In addition, I saw a wonderful programme about Aborigines. (Preliminary English Test; B1; Portuguese)

addition (NEW THING)
B2 C a new or extra thing which is added to something
Dictionary example:

Defender Matt Smith is the latest addition to the team.

Learner example:

There is only one more thing missing: it would be great if there was popcorn provided. I am sure that would be a good addition for everyone. (First Certificate in English; B2; Swiss German)

B2 U the process of adding numbers or amounts together in order to get a total
Dictionary example:

Twice a week the children are tested in basic mathematical skills such as addition and subtraction.

Cambridge University Press