Guidance thrusters are starship components, located each of a ship's nacelles. These components appear to be separate in function from a starship's main thrusters.
The Jem'Hadar fighter discovered by the crew of Deep Space 9 on Torga IV, in 2373, was found in excellent condition, save a crushed guidance thruster – or comparable Dominion component. (DS9: "The Ship")
While preparing for Operation Return in 2374, the USS Cortéz was forced to fall back for repairs after having a continued problem stabilizing the guidance thrusters in the ships port nacelle. (DS9: "Sacrifice of Angels")