ER or Er may refer to:
Ernest Miller Hemingway (July 21, 1899 – July 2, 1961) was an American novelist, short story writer, and journalist.
Eritrea ( or ; Tigrinya: ኤርትራ?, listen ), officially the State of Eritrea, is a country in the Horn of Africa.
Eric Patrick Clapton, CBE (born 30 March 1945), is an English rock and blues guitarist, singer, and songwriter.
The Erie Canal is a canal in New York that is part of the east–west, cross-state route of the New York State Canal System (formerly known as the New York State Barge Canal).
Erich Friedrich Wilhelm Ludendorff (9 April 1865 – 20 December 1937) was a German general, the victor of the Battle of Liège and the Battle of Tannenberg.
EY (formerly Ernst & Young) is a multinational professional services firm headquartered in London, United Kingdom.
ER is an American medical drama television series created by novelist and medical doctor Michael Crichton that aired on NBC from September 19, 1994, to April 2, 2009, with a total of 331 episodes spanning over 15 seasons.