ER or Er may refer to:

Arts, entertainment and media

  • ER (TV series), a 1994–2009 American medical drama series
  • E/R, a 1984–1985 American TV sitcom
  • Er, a character in Plato's Myth of Er
  • Er, a 2005 album by Nils Petter Molvær
  • "ER" (song), a 2012 song by Kanjani Eight
  • "ER", a song by Royce da 5'9" featuring Kid Vishis from the 2011 album Success Is Certain
  • Chico Enterprise-Record, the daily newspaper of Chico, California, US

Businesses and organizations

  • Astar Air Cargo, an American cargo airline, IATA designator ER
  • Eastern Railway zone, in India
  • Estonian Reform Party

Language

  • Er (Cyrillic) (Р р), a letter of the Cyrillic alphabet
  • Er (cuneiform), a sign in cuneiform writing
  • "er", a filler word in English
  • Suffix -er in English:
  • added to adjectives or adverbs to form a comparative (e.g., fast to faster)
  • added to a noun to indicate resident of, as in New Yorker
  • added to a verb to make it an agent noun (e.g., cut to cutter)
  • Oxford "-er", used to form words like rugger and footer
  • R-colored vowel, usually written as "er" in English
  • Erhua, adds er sound to syllables in spoken Mandarin Chinese

People

  • Er (biblical person), the eldest son of Judah in the book of Genesis
  • Nie Er (1912–1935), Chinese composer
  • Elliot Rodger (1991–2014), British-American mass murderer
  • Gültigin Er (born 1997), Turkish triathlete
  • ER, a royal cypher representing a monarch whose name begins with E

Science and technology

Biology and medicine

  • Emergency room, or emergency department, a medical facility
  • Endoplasmic reticulum, a type of organelle in cell biology
  • Er blood group system
  • Equine exertional rhabdomyolysis, in horses
  • Estrogen receptor, a type of protein molecule
  • Extraction ratio, in renal physiology

Chemistry and physics

  • <math>\varepsilon_r</math>, relative permittivity
  • Electrorheological fluid, suspensions of non-conducting but electrically active particles
  • Enantiomeric ratio, in chemistry
  • Erbium, symbol Er, a chemical element
  • Einstein-Rosen bridge, or ER bridge, relativistic wormholes

Computing

  • .er, country code top-level domain for Eritrea
  • Entity–relationship model, a conceptual representation of data
  • Error Resilience, an audio coding method used in MPEG-4 Part 3

Engineering

  • Engine room, a compartment of a ship where the machinery for marine propulsion is located.

Other uses

  • Eritrea, ISO 3166-2 country code ER
  • English Reports of the English Courts from 1220 to 1866

See also

  • ERS (disambiguation)
  • Err (disambiguation)
  • Ur (disambiguation)