- a rocking or oscillating arm or lever rotating with a moving shaft or pivoted on a stationary shaft.
Origin of rocker arm
First recorded in 1855–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for rocker arm
Very suddenly one of them drops out, with a rocker-arm gone.Cavalry of the Clouds
- a lever that rocks about a pivot, esp a lever in an internal-combustion engine that transmits the motion of a pushrod or cam to a valve