Memory Alpha
Memory Alpha

A chronographic sequencer was a device that emitted equally-spaced "tick tocks" to aid in keeping time while playing a piece of music similar to a metronome. (VOY: "Someone to Watch Over Me")

Alternate definition: According to the Star Trek Encyclopedia, 4th ed., vol. 1, p. 143, the chronographic sequencer was a "Borg technical component in drones, allowing them perfect timing and rhythm."