Word forms: (regular plural) rockers
(Mechanical engineering: Machinery and components) A rocker is a device that operates with a rocking motion. ⇒ A rocker switch breaks and connects the electrical circuit by "rocking" in one direction to break the circuit, and in the other direction to connect the circuit. ⇒ As the rocker arm rocks up, it pushes the valve down in the opposite direction. ⇒ A rocker is a device that operates with a rocking motion.
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