Reu or REU may refer to: Places Reu, the local name of Retalhuleu, a city in Guatemala reu, The ISO 3166-1 country code for Réunion REU, The IATA code for Reus Airport in Catalonia, Spain Mount Reu, in Antarctica People Reu, a Biblical figure Papa Reu, a performer Bishweshwar Nath Reu, a historian Johann Michael Reu, a theologian Other uses RAM Expansion Unit, the Commodore 1700/1750/1764 series of memory expansion cartridges for Commodore 64/128 home computers Plekhanov Russian Economic University, a university in Moscow, Russia Research Experiences for Undergraduates, a U.S. National Science Foundation program for students to take part in active research Restricted Enforcement Unit, a UK government committee which controls exports of illegal military material from the United Kingdom