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

Firstly, the signal indicates that WIMPs have a mass around 200 times greater than the mass of a proton. — Robert Lea, Space.com, 2 Sep. 2026

If the event was caused by dark matter, the WIMP would likely have a mass of at least 200 GeV/c2, or more than 200 times the mass of a proton. — Neetika Walter, Interesting Engineering, 1 Sep. 2026

Others have been far too quiet—producing only one billionth the energy of the proton-proton collisions at CERN’s Large Hadron Collider, the most powerful particle accelerator on Earth. — Joseph Howlett, Scientific American, 31 Aug. 2026

As the cosmos cooled and expanded, the free-floating quarks and gluons started binding together to create the building blocks of all matter, including all those necessary atomic protons and neutrons. — Andrew Paul, Popular Science, 20 Aug. 2026

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