Meaning & use
proton
Last updated
Meanings
nouncountablephysicschemistry
A very small particle inside the nucleus of an atom that carries a positive electric charge.
Grammar: Countable: one proton, two protons; it takes a plural and can follow 'a' or a number.
Patterns
- a proton has a positive charge
- the number of protons in an atom
Every atom of carbon has six protons in its nucleus.
Because a proton is positively charged, it is attracted to electrons.
The nucleus contains protons and neutrons packed closely together.
nouncountablephysicschemistrytechnical
This particle considered as the nucleus of ordinary hydrogen, or as a component in particle experiments.
Grammar: Also countable; often used in phrases about beams, collisions, or hydrogen ions.
Patterns
- a beam of protons
- protons collide with something
In the experiment, beams of protons were made to collide at very high speed.
A hydrogen atom that has lost its electron is simply a single proton.
Scientists study what happens when a proton hits a heavy nucleus.
Word forms
| plural | protons |
|---|
Common combinations
- proton number
- The proton number tells you which element an atom is.
- positively charged proton
- A positively charged proton repels another proton.
- proton beam
- The hospital uses a proton beam to treat certain tumors.
- protons and neutrons
- Protons and neutrons together make up the atomic nucleus.
- a single proton
- A hydrogen ion is just a single proton.
Synonyms and how they differ
- hydrogen ion
- In chemistry this often means the same thing as a lone proton, but it is used in acid–base contexts rather than atomic structure.
Opposites
Word family
- protonic adjective
- Relating to protons, as in protonic charge or protonic conduction.
- antiproton noun
- The antimatter partner of a proton, with the same mass but a negative charge.
Commonly confused: proton or electron? proton or neutron?
proton vs electron
An electron is much lighter and carries a negative charge, while a proton sits in the nucleus and is positive.
proton vs neutron
A neutron is about the same mass as a proton but has no electric charge at all.
Practice
Which sentence uses 'proton' correctly?
Choose one answer.
The number of protons identifies the element, so option 0 is right. Electrons orbit the nucleus, not protons (option 1); water is made of atoms, not bare protons (option 2); and protons are positive, not neutral (option 3).
Make it your own
Write a sentence using “proton”, then check it and compare it with the examples above.