(physics) A subatomic particle forming part of the nucleus of an atom and having no charge; it is a combination of an up quark and two down quarks.

plural of neutron

(physics, astronomy) The process, such as within a collapsing star, in which protons and electrons fuse to form neutrons and release neutrinos.

(physics) Relating to neutrons or to neutronics

(physics) The flow of a stream of neutrons

(astronomy) A degenerate star that has been so collapsed by gravity that its electrons and protons have been merged into neutrons by the intense pressure. The solid mass of neutrons is sometimes called neutronium.

(physics, of a nucleus or isotope) Having a large ratio of neutrons to protons

plural of neutron star

An atomic bomb that produces a greater amount of neutrons, and a lesser amount of blast; the intention being to create equal lethal neutron radiation and blast radii which increases the effectiveness of the weapon against armour while reducing collateral damage.

(physics) The general field of study that employs the wavelike character of neutrons.