bulletproof

adjective

bul·​let·​proof ˈbu̇-lət-ˌprüf 

also ˈbə-

1

: impenetrable to bullets

bulletproof glass

2

: not subject to correction, alteration, or modification

a bulletproof argument

3

: invincible

Synonyms of bulletproof

• invincible
• armored
• invulnerable
• impregnable
• unbeatable
• unstoppable
• insurmountable
• indomitable
• unconquerable

Examples of bulletproof in a Sentence

The car has bulletproof windows.

The police officer was wearing a bulletproof vest.

Recent Examples on the Web

Some of the gunfire was captured on video that shows the spray of bulletproof glass as shots hit the 3-inch-thick windshield of an armored vehicle. —Tony Aiello, CBS News, 4 Dec. 2025

Time will tell how bulletproof this model truly is. —Jeremy White, Wired News, 20 Nov. 2025

Uh, and the officer was behind bulletproof glass and [00:40:00] there was a swat vehicle parked out front. —Outside Online, 22 Oct. 2025

Trump appears behind bulletproof glass at memorial Garrett Haake Reporting from Glendale, Ariz. Trump was seen waving from behind bulletproof glass in the skybox above the crowd. —Nbc News, NBC news, 22 Sep. 2025

Word History

First Known Use

1693, in the meaning defined at sense 1

Rhymes for bulletproof

• fireproof
• waterproof
• weatherproof
• aloof
• behoof
• disproof
• flameproof
• foolproof
• greaseproof
• leakproof
• reproof
• soundproof

Kids Definition

bulletproof

adjective

bul·​let·​proof ˈbül-ət-ˌprüf 

: so made as to prevent the passing through of bullets

bulletproof glass