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n. 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.

n. positively charged subatomic particle forming part of the nucleus of an atom and determining the atomic number of an element; the nucleus of the most common isotope of hydrogen; composed of two up quarks and a down quark

n. The first inception or rudiment of a structure or organ in the embryo: a term suggested as an equivalent of the German anlage.

n. A term designating certain products of tryptie digestion which are obtained from the protamins and which, supposedly, are intermediary between these and the end-products.

n. a stable particle with positive charge equal to the negative charge of an electron

"One proton is just like another; but sodium and chlorine are distinct because of the number and arrangement of these parts."

nucleon   

hydrogen ion   

photon   

neutron    electron    photon    hydrogen    hydrogens    neutrino    plasma    atom    gamma    ion