An axion is a hypothetical elementary particle.
Axion may also refer to:
- Axion (mythology), the name of two mythological figures
- Axion (brand), a brand of dishwashing liquid product marketed by Colgate-Palmolive
- Axion (beetle), a genus of lady beetles
- "Axion Estin" or "It is Truly Meet", a hymn of the Eastern Orthodox and Greek-Catholic Churches
- "To Axion Esti", a poem by Odysseas Elytis
- Montreal Axion, a Canadian hockey team
- Cable Axion, a Canadian cable television distributor and Internet service provider
- Claas Axion, a French tractor
- Axion (tribe), a Tribe that existed in Lenape
- Axxion, a guitar model produced by ESP Dave Mustaine