A meson consisting of a quark (usually a charm or a bottom quark) bound to the corresponding antiquark; (as a mass noun) matter consisting of such particles.
Origin
1970s. From quark + -onium.
Definition of quarkonium in US English:
quarkonium
nounkwɑːˈkəʊnɪəm
Particle Physics
A meson consisting of a quark (usually a charm or a bottom quark) bound to the corresponding antiquark; (as a mass noun) matter consisting of such particles.