proton

noun

pro·​ton ˈprō-ˌtän 

: an elementary particle that is identical with the nucleus of the hydrogen atom, that along with the neutron 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 × 10⁻²⁷ kilogram

protonic

prō-ˈtä-nik 

adjective

Examples of proton in a Sentence

Recent Examples on the Web

Nafion itself is usually associated with energy applications such as proton-exchange membranes in fuel cells. —Christopher McFadden, Interesting Engineering, 27 Sep. 2025

Hawking radiation happens even for objects that aren’t black holes, meaning everything, from protons to the entire Universe, will decay. —Ethan Siegel, Big Think, 19 Sep. 2025

So imagine an atom, think of a proton. —Outside Online, 17 Sep. 2025

Because protons and neutrons are shielded from many environmental disturbances, those transitions may carry the subtle imprint of dark matter. —New Atlas, 16 Sep. 2025

Word History

Etymology

Greek prōton, neuter of prōtos first — more at proto-

First Known Use

1920, in the meaning defined above

Phrases Containing proton

• proton pump inhibitor
• proton synchrotron

Rhymes for proton

• anton
• argon
• axon
• baronne
• baryon
• baton
• boron
• buisson
• bygone
• capon
• cardon
• chiffon

Kids Definition

proton

noun

pro·​ton ˈprō-ˌtän 

: an atomic particle that occurs in the nucleus of every atom and carries a positive charge equal in size to the negative charge of an electron

protonic

prō-ˈtän-ik 

adjective

Medical Definition

proton

noun

pro·​ton ˈprō-ˌtän 

: 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

protonic

prō-ˈtän-ik 

adjective