The story
Blend of electric + ion, coined by Anglo-Irish scientist George Stoney in 1891, changed by him multiple times from an earlier electrolion and original electrine (used as early as 1874) as the name for the electric charge associated with a univalent ion. Compare electro-, -on. The particle ("corpuscule") was discovered in 1896. The name electrion was proposed for the particle in 1906 but curtailed because Hendrik Lorentz preferred electron.
Etymology from Wiktionary, CC BY-SA 4.0.