Definition of "Rocker" :

noun: a curved support that permits the supported object to rock to and fro

noun: an ice skate with a curved blade

noun: 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

noun: a chair mounted on rockers

noun: a teenager or young adult in the 1960s who wore leather jackets and rode motorcycles

noun: a performer or composer or fan of rock music

noun: an attendant who rocks a child in a cradle