-TRON Meaning of -TRON in English ■ suffix Physics1》 denoting a subatomic particle: positron.2》 denoting a particle accelerator: cyclotron.3》 denoting a thermionic valve: ignitron. Originfrom (elec)tron . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004