particle beam

American  

noun

1. Physics. a concentrated stream of particles, as electrons, neutrons, or protons, generated for studying particle interactions, nuclear structure, crystal structure, etc.

2. Military. a high-energy stream of such particles for use as a weapon or for antimissile defense.

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particle beam British  

noun

1. a stream of energized particles produced by a particle accelerator

2. such a stream emitted by a particle beam weapon

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