• An alternate symbol for the international unit
  International unit
  In pharmacology, the International Unit is a unit of measurement for the amount of a substance, based on biological activity or effect. It is abbreviated as IU, as UI , or as IE...
  
   (IU)
• Eurocypria Airlines
  Eurocypria Airlines
  Eurocypria Airlines Limited was a charter airline based in Larnaca, Cyprus, owned by the government of Cyprus, operating mostly chartered flights. Its main base was Larnaca International Airport, with a secondary base at Paphos International Airport. On 4 November 2010 it was announced that the...
  
  , IATA airline designator
• Unemployment Insurance
• The United Illuminating Company
  The United Illuminating Company
  The United Illuminating Company is a New Haven, Connecticut-based regional electric distribution company established in 1899. UI is engaged in the purchase, transmission, distribution and sale of electricity and related services to 325,000 residential, commercial and industrial customers in 17...
  
  
• United Ireland
  United Ireland
  A united Ireland is the term used to refer to the idea of a sovereign state which covers all of the thirty-two traditional counties of Ireland. The island of Ireland includes the territory of two independent sovereign states: the Republic of Ireland, which covers 26 counties of the island, and the...
  
  
• Universal indicator
  Universal indicator
  A Universal indicator is a pH indicator composed of a blend of several compounds that exhibits several smooth colour changes over a pH value range from 1-14 to indicate the acidity or basicity of solutions. Although there are a number of commercially available universal pH indicators, most are a...
  
  
• Universities Ireland
  Universities Ireland
  Universities Ireland is an organisation which promotes collaboration and co-operation between universities in Ireland, including those both in Northern Ireland and in the Republic of Ireland...
  
  
• Unix International
  Unix International
  Unix International or UI was an association created in 1988 to promote open standards, especially the Unix operating system. Its most notable members were AT&T and Sun Microsystems, and in fact the commonly accepted reason for its existence was as a counterbalance to the Open Software Foundation ,...
  
  
• Unit Injector
  Unit Injector
  Unit Injector is an integrated direct fuel injection system for diesel engines, combining the injector nozzle and the injection pump in a single component...
  
  , a fuel injection technology for diesel engines
• Urinary incontinence
  Urinary incontinence
  Urinary incontinence is any involuntary leakage of urine. It is a common and distressing problem, which may have a profound impact on quality of life. Urinary incontinence almost always results from an underlying treatable medical condition but is under-reported to medical practitioners...
  
  
• User interaction
• User interface
  User interface
  The user interface, in the industrial design field of human–machine interaction, is the space where interaction between humans and machines occurs. The goal of interaction between a human and a machine at the user interface is effective operation and control of the machine, and feedback from the...
  
  
• Ui (digraph), a digraph used in some writing systems
• Ui, an ancient Phoenician colony located at the site of modern-day Tripoli
  Tripoli
  Tripoli is the capital and largest city in Libya. It is also known as Western Tripoli , to distinguish it from Tripoli, Lebanon. It is affectionately called The Mermaid of the Mediterranean , describing its turquoise waters and its whitewashed buildings. Tripoli is a Greek name that means "Three...
  
   in Libya
• Arturo Ui, a fictional character from The Resistible Rise of Arturo Ui
  The Resistible Rise of Arturo Ui
  The Resistible Rise of Arturo Ui is a play by the German dramatist Bertolt Brecht, originally written in 1941...
  
  by Bertolt Brecht
• Ui (band)
  Ui (band)
  Ui is an American post-rock/funk band based in New York City, which started in 1990. The group was started by Sasha Frere-Jones and Clem Waldmann. Wilbo Wright joined the group in 1993. The group's songs are often described as "bass-heavy", as the band frequently uses two bass guitars. Other...
  
  , an American post-rock band
• Utility infielder
  Utility infielder
  A utility infielder is a baseball player, usually one who does not have a regular starting role on the team and who is capable of playing more than one of the four defensive infield positions: second base, third base, shortstop, and less typically first base...
  
  , baseball player

• University of Iceland
  University of Iceland
  The University of Iceland is a public research university in Reykjavík, Iceland, and the country's oldest and largest institution of higher education. Founded in 1911, it has grown steadily from a small civil servants' school to a modern comprehensive university, providing instruction for about...
  
  
• University of Innsbruck
• University of Indonesia
  University of Indonesia
  The Universitas Indonesia, is a state, comprehensive world class university located in Depok, West Java and Salemba, Jakarta, Indonesia. Universitas Indonesia is the oldest tertiary-level educational institution in Indonesia...
  
  
• University of Ibadan
  University of Ibadan
  The University of Ibadan is the oldest Nigerian university, and is located five miles from the centre of the major city of Ibadan in Western Nigeria...
  
  , Nigeria
• University of Idaho
  University of Idaho
  The University of Idaho is the State of Idaho's flagship and oldest public university, located in the rural city of Moscow in Latah County in the northern portion of the state...
  
  
• University of Illinois
  University of Illinois system
  The University of Illinois is a system of public universities in Illinois consisting of three campuses: Urbana-Champaign, Chicago, and Springfield. Across its three campuses, the University of Illinois enrolls about 70,000 students. It had an operating budget of $4.17 billion in 2007.-System:The...
  
  
• University of Iowa
  University of Iowa
  The University of Iowa is a public state-supported research university located in Iowa City, Iowa, United States. It is the oldest public university in the state. The university is organized into eleven colleges granting undergraduate, graduate, and professional degrees...
  
  
• University of Isfahan
  University of Isfahan
  University of Isfahan is a state-operated university in Iran. It is one of the most prominent science and engineering schools in Iran and is the largest university in Isfahan Province in Iran. The university is located in the southern section of the city of Isfahan...
  
  

• Ui Hirasawa, a fictional character in the anime and manga series K-On!
  K-On!
  is a Japanese four-panel comic strip manga written and illustrated by Kakifly. The manga was serialized in Houbunsha's seinen manga magazine Manga Time Kirara between the May 2007 and October 2010 issues. It was also serialized in Houbunsha's magazine Manga Time Kirara Carat...
  
  

See also

• μ_i, The initial magnetic permeability
  Permeability (electromagnetism)
  In electromagnetism, permeability is the measure of the ability of a material to support the formation of a magnetic field within itself. In other words, it is the degree of magnetization that a material obtains in response to an applied magnetic field. Magnetic permeability is typically...
  
  of a material