| a positively charged elementary particle that is a fundamental constituent of all atomic nuclei. It is the lightest and most stable baryon, having a charge equal in magnitude to that of the electron, a spin of 1/2 , and a mass of 1.673 × 10−2 7 kg. Symbol: P |
pro·ton (prō'tŏn') n. Abbr. p A stable, positively charged subatomic particle in the baryon family having a mass 1,836 times that of the electron. See Table at subatomic particle. [From Greek prōton, neuter of prōtos, first; see per1 in Indo-European roots.] pro·ton'ic adj. |
proton pro·ton (prō'tŏn')
n.
A stable, positively charged subatomic particle in the baryon family having a mass 1,836 times that of the electron.