You searched for: “quantum chromodynamics
chromodynamics, quantum chromodynamics
1. A quantum field theory of elementary particles that states that the color properties of quarks (small particles of an atom) are bound together by gluons.
2. The physics of the relationship between color-carrying quarks, especially the nature of their strong interaction, which is characterized by the exchange of gluons.

Gluons are theoretical elementary particles without mass, thought to be involved in binding the subatomic particles of quarks together.