1. 电视（节目）观众
    Viewers are people who watch television, or who are watching a particular programme on television.

2. 观看者;观察者
    A viewer is someone who is looking carefully at a picture or other interesting object.

3. （看幻灯片的）观片器，看片器
    A viewer is a device shaped like a box with a lens in one side. It is used for looking at transparent colour photographs.

1. an optical device for viewing photographic transparencies

2. a close observer
    someone who looks at something (such as an exhibition of some kind)

    e.g. the spectators applauded the performance
           television viewers
           sky watchers discovered a new star

    Synonym: spectatorwitnesswatcherlooker