ER or Er may refer to:
Ernest Miller Hemingway (July 21, 1899 – July 2, 1961) was an American journalist, novelist, short-story writer, and sportsman.
Eric Patrick Clapton, (born 30 March 1945) is an English rock and blues guitarist, singer, and songwriter.
Eritrea (; (listen); Tigrinya: ኤርትራ), officially the State of Eritrea, is a country in the Horn of Africa, with its capital at Asmara.
Errol Leslie Thomson Flynn (20 June 1909 – 14 October 1959) was an Australian-born American actor during the Golden Age of Hollywood.
The Erie Canal is a canal in New York, United States 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).
In earth science, erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location (not to be confused with weathering which involves no movement).
Johannes Erwin Eugen Rommel (15 November 1891 – 14 October 1944) was a German general and military theorist.
Desiderius Erasmus Roterodamus (; 28 October 1466 – 12 July 1536), known as Erasmus or Erasmus of Rotterdam, was a Dutch philosopher and Christian humanist who is widely considered to have been the greatest scholar of the northern Renaissance.