re‧place‧ment W3 / rɪpleɪsmənt / 名词

1 [不可数名词] when you get something that is newer or better than the one you had before :

Our old car is badly in need of replacement.

replacement windows

2 knee/hip/joint replacement an artificial knee etc that replaces a damaged one, given to people in a medical operation

3 [可数名词] someone or something that replaces another person or thing

replacement for

It was difficult to find a replacement for Ted.