Definition of neutron in English:


Pronunciation /ˈn(y)o͞oträn/ /ˈn(j)utrɑn/

Translate neutron into Spanish


  • A subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.

    ‘Even the protons and neutrons in the atomic nucleus are believed to made of even smaller particles called quarks.’
    • ‘The result would be a star made entirely of neutrons, and these could be packed together as closely as the protons and neutrons in an atomic nucleus.’
    • ‘If conditions are right, protons and electrons then fuse into neutrons, creating a neutron star.’
    • ‘The mass number gives you the total number of protons and neutrons in the nucleus of that element.’
    • ‘An alpha particle consists of two protons and two neutrons; it is the nucleus of a helium atom.’


Early 20th century from neutral+ -on.