a stream of molecules freed from a substance, usually a salt, by evaporation and then passed through a narrow slit for focusing, for investigating the properties of nuclei, atoms, and molecules.
Also called molecular ray.
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physics a parallel beam of molecules that are at low pressure and suffer no interatomic or intermolecular collisions
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