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Medical Dictionary


noun pro·ton \ˈprō-ˌtän\

Medical Definition of PROTON

:  an elementary particle that is identical with the nucleus of the hydrogen atom, that along with neutrons is a constituent of all other atomic nuclei, that carries a positive charge numerically equal to the charge of an electron, and that has a mass of 1.673×10−24 gram
pro·ton·ic \prō-ˈtän-ik\ adjective
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