This is the 236th most frequent Japanese word.
協力
Cooperation.
Here, '協力' (cooperation) is used as a verb to indicate working together towards a common goal.
私たちはこのプロジェクトの成功のために協力する必要があります。
We need to cooperate for the success of this project.
In this instance, '協力' (cooperation) functions as a noun, referring to the act of mutually working together.
彼の協力がなければ、この成果は達成できなかったでしょう。
Without his cooperation, this achievement would not have been possible.
Here, '協力' is used as a noun, specifying the contribution or assistance required from everyone.