'nucleon' originates from a modern English formation, specifically from 'nucleus' + the particle-forming suffix '-on' (from Greek '-on'), where 'nucleus' originally meant 'kernel' or 'little nut' in Latin.

'nucleon' was coined in the 20th century (mid-1900s) to name the constituents of the atomic nucleus (protons and neutrons), formed by combining the already-established scientific word 'nucleus' with the particle suffix '-on' (as in 'proton', 'electron').

Initially, the root 'nucleus' meant 'kernel' or 'little nut'; 'nucleon' was created to mean 'a particle of the nucleus' and has retained that specialized physics meaning.