Magnetic interlock

From Memory Alpha, the free Star Trek reference.

Magnetic interlocks form part of the warp drive system aboard starships, as part of the warp core assembly. Magnetic interlocks can be disrupted by subspace vacuoles. (VOY: "Emanations")

During the battle with the Duras sisters in 2371, the starboard interlock of the USS Enterprise-D took damage, and required reinforcement. Subsequently, the interlocks ruptured, leading to a coolant leak, and eventually a warp core breach that destroyed the secondary hull. (Star Trek Generations)

Following sabotage by the True Way to the USS Orinco, the magnetic interlocks on the runabout failed, leading to a warp core breach. (DS9: "Our Man Bashir")