ER

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, a 2021 album by The Kleptones
• "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

• $\varepsilon _{r}$, 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

• All pages with titles containing ER or ERs
• All pages with titles containing e-r
• All pages with titles beginning with ER
• All pages with titles beginning with er
• ERS (disambiguation)
• Err (disambiguation)
• Ur (disambiguation)