Англо-русский словарь по авиации. 2013.
jamproof — /jam proohf /, adj. built so as to prevent jamming: a jamproof copying machine. [JAM1 + PROOF] * * * … Universalium
jamproof — /jam proohf /, adj. built so as to prevent jamming: a jamproof copying machine. [JAM1 + PROOF] … Useful english dictionary