RO

• Ro (company), an American telehealth company
• Royal Ordnance, a British armaments manufacturer
• TAROM, a Romanian airline, IATA airline code RO

• Rø, Denmark
• Ro, Emilia-Romagna, Italy
• Ro, Greece, a small Greek island
• Romania (ISO 3166-1 country code RO)

• .ro, Internet country code top-level domain for Romania
• Ro (antigen)
• Autoantigen Ro, a protein
• Ro (volume), an Egyptian unit of measurement
• Radio occultation, a technique for measuring the properties of an atmosphere
• Reactor operator, a person who controls a nuclear reactor
• Reverse osmosis, a water purification process
• Receive only, a type of teleprinter
• Anti-SSA/Ro autoantibodies (anti–Sjögren's-syndrome-related antigen A autoantibodies)

• Ro (kana), a Japanese character
• Ro (name), a given name, nickname and surname
• Ro (dubious Danish king)
• Ro (pharaoh) or Iry-Hor (fl. c. 3170 BC), Egyptian pharaoh
• Ro (title), a Fijian title of nobility
• Ro (video game), 2008
• Ro language, a constructed language
• Rö Church, in Stockholm County, Sweden
• Romanian language, ISO 639-1 language code ro
• Range Officer, supervising a shooting range
• Renewables Obligation (United Kingdom), a British order requiring renewable electricity generation

• R0 (disambiguation)
• Rho (disambiguation)
• ROH (disambiguation)
• Roll-on/roll-off, or RORO, cargo ships carrying wheeled cargo

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