one of the two curved pieces of wood on the bottom of a rocking chair （摇椅底部的）弧形摇杆 
- (especially North American English) (also rocking chair British and North American English)
a chair with two curved pieces of wood under it that make it move backwards and forwards 摇椅 - Rocker(British English)
a member of a group of young people in the UK, especially in the 1960s, who liked to wear leather jackets, ride motorcycles and listen to rock and roll music 摇滚青年（尤指 20 世纪 60 年代的某些英国青年，喜欢穿皮夹克、骑摩托车、听摇滚乐） a person who performs, dances to or enjoys rock music 摇滚乐表演者；跳摇滚舞的人；喜欢摇滚乐的人 a concert by ageing rocker, Rod Stewart 老摇滚歌手洛德·斯蒂沃特的音乐会
Idioms
be off your rocker
- (informal)
to be crazy 发疯；疯狂