A pion is a type of subatomic particle.

Pion may also refer to:

• PION, gene; see Protein pigeon homolog
• 2S7 Pion, self-propelled gun
• Pión District, in Peru
• Posterior ischemic optic neuropathy
• Pio Pion (1887–1965), Italian entrepreneur
• Pion, Asturias, a parish in Villaviciosa, Asturias, Spain.

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