synchronizer

noun

One who or that which synchronizes; especially, a contrivance for synchronizing clocks. Also spelled synchroniser.

noun

In electricity, an apparatus for indicating when two alternating-current machines are revolving at the same speed.

noun

One who/which synchronizes.

noun

an instrument that indicates whether two periodic motions are synchronous (especially an instrument that enables a pilot to synchronize the propellers of a plane that has two or more engines)