/kə,læbə'reɪʃn; kə,læbə`reʃən/
n [U]
1 ~ (with sb) (on sth); ~ (between A and B) collaborating (collaborate 1) 合作; 协作
*She wrote the book in collaboration with her sister, ie They wrote it together. 她和姐姐合作写成此书.
2 ~ (with sb) helping enemy forces occupying one's country 通敌.

n
[U and C]
when you work together with another person or group to achieve something, especially in science or art
　The company is building the centre in collaboration with the Institute of Offshore Engineering.
collaboration between
　a collaboration between the two theatres
collaboration with
　The project has involved collaboration with the geography department.
[U]
when someone gives help to a country that their country is fighting a war with, especially one that has taken control of their country