What does "rocker" mean?

Rocker: One of the curving pieces of wood or metal on which a cradle, chair, etc., rocks.

Additional senses

  1. 2.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.
  2. 3.A play horse on rockers; a rocking-horse.
  3. 4.A chair mounted on rockers; a rocking-chair.
  4. 5.A skate with a curved blade, somewhat resembling in shape the rocker of a cradle.
  5. 6.(Mach.) Same as Rock shaft. Rocker arm (Mach.), an arm borne by a rock shaft. To be off one's rocker, to be insane.

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