RI

• Ri, a common Korean surname, a variant romanization of Lee • Rí (rig), an ancient Gaelic word meaning "king" • Ri (pronoun), a gender-neutral pronoun in Esperanto • RI, an initialism of Rex Imperator (king-emperor) or Regina Imperatrix (queen-empress), used by those British monarchs who were rulers of both the United Kingdom and the Indian Empire ==Places==

• Ri (administrative division), an administrative unit in both North Korea and South Korea • Ri, Orne, a commune of the Orne département in France • RI, abbreviation of either the Republic of Indonesia or, in the Indonesian language, Republik Indonesia • Rhode Island, a state within the US (postal abbreviation RI) • Rijeka, city in Croatia ==Arts and media==

• Ri, an augmented second in solfege, used in music education • Ri, a representation of the second svara in Indian classical music • Russia Insider, a pro-Kremlin news and propaganda website ==Businesses and organizations==

• Raffles Institution, a school in Singapore • Refugees International, an international humanitarian organization • Rehabilitation International, an international disability rights organization • Rotary International, international organization of business and professional leaders focused on non-political and non-sectarian humanitarian service • Royal Institution of Great Britain, an organisation devoted to scientific education and research • Royal Institute of Painters in Water Colours, a society in the Federation of British Artists • Chicago, Rock Island and Pacific Railroad (reporting mark RI) • Tigerair Mandala (IATA airline designator RI) • Italian Radicals, a political party in Italy ==Science, technology, and mathematics==

• Ri (prefix symbol), a binary unit prefix symbol • Reference Intake, a food labelling system • Referential integrity, a database concept • Refractive index of an optical medium (in physics/optics) is a number that describes how light propagates through that medium • Arterial resistivity index, a measure of pulsatile blood flow • Ring Indicator, a signal in the RS232 serial communications standard • Rhombicosahedron, a polyhedron, by Bowers acronym • Residual income, a financial profitability measure of a company • Reputation Institute, a research and insights company that analyzes the reputation of corporations and places • Rapid intensification, a phenomenon in which the wind speed of a tropical cyclone increases dramatically in a short period of time • Research institute, an establishment founded for doing research ==Other uses==

• Ri (cuneiform), a cuneiform sign • Ri (kana), a Romanization of the Japanese kana り and リ • Ri, a unit of measurement in Japan and Korea related to the Chinese li • Rock Island District, a commuter rail line on Chicago's Metra (abbreviated as RI on maps and schedules) ==See also==