Tricyclic plasma drive

From Memory Alpha, the free Star Trek reference

The tricyclic plasma drive was a type of propulsion system utilized by some Suliban stealth ships during the 2150s.

Use of tricyclic plasma drives created spatial disturbances. If one measured the decay rate of the plasma, it would possible to follow the ship's warp trail. Commander Trip Tucker suggested this method when a Suliban vessel abducted Klaang from Enterprise, but the ship's sensors had to be modified to measure plasma decay. (ENT: "Broken Bow")