Although not exactly a universally accepted terminology, since it's seldom needed, in the science of mechanics and dynamics the rate at which an object changes position (dx/dt if x is position and t is time) is called velocity.

The rate at which velocity changes (dv/dt = d²x/dt²) is called the acceleration.

The rate at which acceleration changes (da/dt = d²v/dt² = d³x/dt3) is called the jerk value.

The rate at which the jerk changes (d⁴x/dt4) is called the zing value.

The rate of change of the zing ((d⁵x/dt5) is called the twitch.

And the rate of change of the twitch (d³x/dt3) is called the snap.

Position, velocity, acceleration, jerk, zing, twitch, snap.

The "higher derivative" terms are seldom encountered, since once an observable jerk is present something nearly always breaks and the experiment is over.

("(s)he's got a lot of zing" means the person is "unpredictably jerky" but is not usefully used except in small and usually isolated "cliques" of narrowly specialized pseudo-mathematicians. Describing a person as "twitchy" in such a group would likely not be deemed complimentary.)

Obviously this is not the "mechanical twitch" found in the subject song though, so the thread should continue with the more applicable discussion.

John