Main Entry: pro·ton

Pronunciation: \ˈprō-ˌtän\

Function: noun

: 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