| Bombproof 1. (a.) Secure against the explosive force of bombs. 2. (n.) A structure which heavy shot and shell will not penetrate. Thesaurus Entries ballproof, bombproof, bulletproof, burglarproof, close, compact, corrosionproof, dampproof, dustproof, dusttight, fast, fire-resisting, fireproof, firm, flameproof, foolproof, gasproof, gastight, hermetic, hermetically sealed, holeproof, impervious to, leakproof, lightproof, lighttight, noiseproof, oilproof, oiltight, proof, proof against, punctureproof, rainproof, raintight, resistant, rustproof, sealed, shatterproof, shellproof, shut fast, smokeproof, smoketight, snug, soundproof, staunch, stormproof, stormtight, tight, water-repellant, waterproof, watertight, weatherproof, windproof, windtight | ![]() |