mesotron
nounUK /ˈmɛs.əˌtɹɒn/ · US /ˈmɛs.əˌtɹɑn/
Etymology From meso- + -tron. Coined by American physicists Carl Anderson and Seth Neddermeyer in 1938 in a letter to Nature titled "Mesotron (Intermediate Particle) as a Name for the New Particles of Intermediate Mass".