line manager
noun uk/ˈlaɪn ˌmæn.ɪ.dʒər/ us/ˈlaɪn ˌmæn.ə.dʒɚ/
someone's line managermainly UK （某人的）顶头上司，部门经理
the person who is directly responsible for managing the work of someone else in a company or business, and who is one level above that person
（负责生产等主要活动的）主管经理
one of the managers who are responsible for the most important activities of a large company, such as production