Skip to Content


Pronunciation: pro'ton

Definition: The positively charged unit of the nuclear mass; protons form part (or in hydrogen 1 the whole) of the nucleus of the atom around which the negative electrons revolve.

[G. ntr. of protos, first]

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.