bulletproof

Strong enough to stop bullets from passing through it.

• The guard wore a bulletproof vest.
• The car has bulletproof windows.
• They installed bulletproof glass at the entrance.

Similar words: bullet-resistant

Common phrases: bulletproof vest, bulletproof glass, bulletproof jacket

So strong or well supported that it is very difficult to damage, attack, or disprove.

• Her argument seemed bulletproof.
• The lawyer built a bulletproof case.
• Even his strongest critics could not challenge that bulletproof alibi.

Similar words: unassailable, watertight, solid

Opposites: weak, vulnerable

Common phrases: bulletproof argument, bulletproof case, bulletproof alibi

Very reliable and able to keep working even when problems occur.

• We need a bulletproof backup system.
• The software is fast, but it isn't bulletproof.
• Their bulletproof design kept the service running during the power failure.

Similar words: reliable, robust, fail-safe

Opposites: unreliable, fragile

Common phrases: bulletproof system, bulletproof software, bulletproof design

To improve something so that it continues to work properly even when problems occur.

• We need to bulletproof this software.
• The team bulletproofed the payment system before launch.
• Testing unusual inputs helps us bulletproof the program.

Similar words: strengthen, make robust

Common phrases: bulletproof the system, bulletproof your code, bulletproof a process

To change something so that bullets cannot pass through it.

• They plan to bulletproof the car.
• The company bulletproofed all the vehicle's doors.
• Can these windows be bulletproofed without replacing the frames?

Common phrases: bulletproof a car, bulletproof the doors, bulletproof a vehicle