'meson' originates from Greek, specifically the element 'meso-' from Greek 'mesos', where 'meso-' (or 'mesos') meant 'middle'; the particle-suffix '-on' (from New Latin/Greek) was appended.

'meson' was coined in the 1930s (seen in forms like 'mesotron') to denote an intermediate-mass particle; the term was later shortened to 'meson' and retained in modern particle nomenclature for quark-antiquark hadrons.

Initially, it meant 'an intermediate-mass particle' (and was used for the muon/mesotron); over time it narrowed to its current meaning of 'a hadronic quark–antiquark particle' such as pions and kaons.