bulletproof

adj

1. Capable of withstanding a direct shot by a bullet fired from a gun.

   “bulletproof window”

   “bulletproof vest”

   “bulletproof car.”

   “YouTube is awash in gun content, often referred to as “GunTube” by firearm enthusiasts. Individuals who come to GunTube—including children and teens—can find videos which glorify assault weapons, show how to modify firearms, and teach viewers how to shoot through bulletproof glass or “win gunfights.””

2. (figuratively)Reliable, infallible, sturdy or error-tolerant.

   “bulletproof hosting”

   “The packed opening night of Twain’s first UK tour since 2004 is an impressively barnstorming, thigh-slapping, eye-searing revue that marries her bulletproof back catalogue with a cautious sprinkle of new material.”

   “But what tone indicators lack in artfulness, they make up for in their bulletproof inability to be misinterpreted.”

verb

1. (transitive)To make proof against bullets.
2. (informal, transitive)To make resistant to failure.

   “We have to bulletproof this program before we let the users at it; check every input, catch every possible flaw... it must not fail in use.”

noun

1. (slang)A liquor store

   “I converted it to a mini-bar and then I went to every single bulletproof in my neighborhood and ordered a ridiculous amount.”