ad‧di‧tion S3 W1 / ədɪʃ ə n / 名词

1 in addition used to add another piece of information to what you have just said :

The company provides cheap Internet access. In addition, it makes shareware freely available.

in addition to something

In addition to his movie work, Redford is known as a champion of environmental causes.

2 [不可数名词] the act of adding something to something else

the addition of something

The addition of networking facilities will greatly enhance the system.

with the addition of something

Turn sparkling wine into Buck’s Fizz with the addition of chilled orange juice.

3 [可数名词] something that is added to something else, often in order to improve it

addition to

This excellent book will be a welcome addition to the library of any student.

latest/new/recent addition

the latest addition to our designer range

4 [不可数名词] the process of adding numbers or amounts to make a total → subtraction

5 [可数名词] American English an extra room that is added to a building :

They built a big addition onto the back of the house.