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Synonyms

bulletproof

American  
[bool-it-proof] / ˈbʊl ɪtˌpruf /

adjective

  1. (of vehicles, glass, clothing, etc.) capable of resisting or absorbing the impact of a bullet.

  2. Informal. safe from failure; without errors or shortcomings and beyond criticism.

    a bulletproof system; a bulletproof budget.

verb (used with object)

  1. to make (something) bulletproof.

bulletproof British  
/ ˈbʊlɪtˌpruːf /

adjective

  1. not penetrable by bullets

    bulletproof glass
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. (tr) to make bulletproof

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of bulletproof

First recorded in 1855–60; bullet + -proof

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Bulletproof glass encasing the portico for his annual appearance with the Easter Bunny?

From Slate • Apr. 28, 2026

Longevity biohacker and Bulletproof Coffee founder Dave Asprey started integrating EMS into his routine more than a decade ago.

From The Wall Street Journal • Apr. 1, 2026

Nicholson, who has an M.B.A. from Northwestern’s Kellogg School of Management, says that Bulletproof, a family office that manages money for a wealthy individual, invests in both public and private markets.

From Barron's • Jan. 31, 2026

Outstanding Directing for a Comedy Series: "Abbott Elementary" — "Party" "The Bear" — "Fishes" "The Bear" — "Honeydew" "The Gentlemen" — "Refined Aggression" "Hacks" — "Bulletproof" "The Ms. Pat Show" — "I’m the Pappy"

From Salon • Sep. 15, 2024

Your Tandem is become far more renowned than the Bulletproof coach, and your horse Bob, is far more famous already than the charger of old Blucher.

From Memoirs of Henry Hunt, Esq. — Volume 3 by Hunt, Henry

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.