proton
noun /ˈprəʊtɒn/
/ˈprəʊtɑːn/
(physics)- a very small piece of matter (= a substance) with a positive electric charge that forms part of the nucleus (= central part) of an atom see also electron, neutronWordfinderTopics Physics and chemistryc2
- antiparticle
- atom
- electron
- ion
- neutron
- nucleus
- particle
- positron
- proton
- valency
Word Origin1920s: from Greek, neuter of prōtos ‘first’.