a person who tries to prevent or stop arguments or fighting between two or more people or groups

At school he was what they call a peacekeeper. He would always make sure everyone was getting along. 在学校里，他是大家所谓的和事佬，总是确保每个人都融洽相处。

a member of an international military force whose job is to prevent or stop fighting in a place

UN peacekeepers were brought in to the troubled area. 联合国维和部队被派往动乱地区。

Since then, the territory has been run by the UN and protected by about 8,000 international peacekeepers. 从那时起，这片领土一直由联合国管理，并由约8000名国际维和士兵保护。