Read the dictionary definition of rocker. All definitions for this word.
1. a curved support that permits the supported object to rock to and fro
2. an ice skate with a curved blade
3. a trough that can be rocked back and forth; used by gold miners to shake auriferous earth in water in order to separate the gold
4. a chair mounted on rockers
5. a teenager or young adult in the 1960s who wore leather jackets and rode motorcycles
6. a performer or composer or fan of rock music
7. an attendant who rocks a child in a cradle