Force field

An energy shield, sometimes called a forcefield, is a device used for purposes of defending an object or location, or serving as a means of imprisonment.

Animated continuity
After being captured by the Decepticons, Spike Witwicky was held in a force field to prevent him from escaping. Still, the Decepticons had Ravage remain to keep an eye on him.

Beast Wars
After being on Earth for some time, Rhinox developed a shield system as part of Sentinel's security systems. The shields could stand up to a heavy amount of punishment, though at times it inevitably failed. After the Axalon sank into the river near it, the Maximals attempted to salvage Sentinel, but the Predacons managed to steal the control system and installed it in the Darksyde, simultaneously managing to bolster their own defenses and putting the Maximals on a defensive footing for the remainder of the Beast Wars.

After moving into Mount St. Hilary, the Maximals attempted to use Teletraan I to power their shields, but Autobot technology and Maximal technology were too different to make a compatible system, leading to the aforementioned salvage attempt.

Beast Machines
Megatron installed powerful shields aboard the Grand Mal, which were the only defense the Maximals could activate when the Vehicons attempted to take the vessel back. The shields, however, cut Botanica off from Cybertron's organic core. To save her, Rattrap launched in an escape pod containing a shield emitter which mimiced the Grand Mal's own shield harmonics. Megatron found the emitter, and transmitted the harmonics to Obsidian, whose forces shot the Grand Mal out from the sky.