Look up peo in Wiktionary, the free dictionary.

PEO may stand for:

• Parking enforcement officer, an official who issues parking tickets
• Plasma electrolytic oxidation, a surface-treatment process for metals
• Polyethylene oxide, alternate name for Polyethylene glycol, a polymer
• Old Persian, ISO 639-2 and ISO 639-3 language code peo
• Pancyprian Federation of Labour, an umbrella organization for trade unions in Cyprus (Greek: Παγκύπρια Εργατική Ομοσπονδία, Pankypria Ergatiki Omospondhia)
• P.E.O. Sisterhood, an international women's organization with headquarters in North America
• Professional employer organization, a service provider of outsourced human resource management
• Professional Engineers Ontario, professional and regulatory organization for engineers in Ontario, Canada
• Program executive officer, an individual, civilian or military, responsible for large scale U.S. military acquisitions
• Programs Evaluation Office, a covert U.S. paramilitary mission in Laos in 1955-1962
• Progressive external ophthalmoplegia, alternate term for chronic progressive external ophthalmoplegia, an eye disorder