someone whose job is to look after or help customers in a public place.——朗文当代大辞典

someone who looks after a very important person, for example a king or queen.——朗文当代大辞典

One who waits upon, accompanies, or follows another in order to render service; one of a retinue or train; a servant, satellite, subordinate companion.——牛津当代大辞典  @en