neutron
nounUK /ˈnjuː.trɒn/
US /ˈnuː.trɑːn/
A tiny piece inside the center of an atom that has no electric charge.
A neutron and a proton together make up most of an atom's mass.
OTHER MEANINGS
2. A particle in the nucleus of an atom that is about the same size as a proton but carries no charge.
The nucleus of carbon-12 contains six protons and six neutrons.
3. A neutral subatomic particle that can travel far through matter before interacting.
Neutron beams are used to study the structure of materials.
4. A particle released during nuclear fission that can trigger further fission in a chain reaction.
Each fission event releases neutrons that can split more uranium atoms.