(a person who is) involved in or connected with improving people's lives and reducing suffering

The prisoner has been released for humanitarian reasons. 出于人道主义原因那名囚犯被释放了。

The United Nations is sending humanitarian aid (= food and supplies to help people) to the areas worst affected by the conflict. 联合国正在向受冲突影响最为严重的地区输送人道主义援助。

The well-known humanitarian, Joseph Rowntree, was concerned with the welfare of his employees. 著名的人道主义者约瑟夫‧荣特里非常关心其雇员的福利。