alpha particle

noun

Definition of alpha particle

:a positively charged nuclear particle identical with the nucleus of a helium atom that consists of two protons and two neutrons and is ejected at high speed in certain radioactive transformations called also alpha, alpha radiation, alpha ray

First Known Use of alpha particle

1903



Medical Dictionary

alpha particle

noun

medical Definition of alpha particle

:a positively charged nuclear particle identical with the nucleus of a helium atom that consists of two protons and two neutrons and is ejected at high speed in certain radioactive transformations called also alpha, alpha ray

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