rocker

n. 1. One who rocks; specifically, one who rocks a cradle. [ 1913 Webster ]

It was I, sir, said the rocker, who had the honor, some thirty years since, to attend on your highness in your infancy. Fuller. [ 1913 Webster ]

2. One of the curving pieces of wood or metal on which a cradle, chair, etc., rocks. [ 1913 Webster ]

3. Any implement or machine working with a rocking motion, as a trough mounted on rockers for separating gold dust from gravel, etc., by agitation in water. [ 1913 Webster ]

4. A play horse on rockers; a rocking-horse. [ 1913 Webster ]

5. A chair mounted on rockers; a rocking-chair. [ 1913 Webster ]

6. A skate with a curved blade, somewhat resembling in shape the rocker of a cradle. [ 1913 Webster ]

7. (Mach.) Same as Rock shaft. [ 1913 Webster ]

Rocker arm (Mach.), an arm borne by a rock shaft. [ 1913 Webster ]