noun

• (US) An elevated railway, especially for specific systems such as the metro in Chicago (informal)
  "The main section of the Sixth Avenue El from Morris Street to Ninth Avenue and 53rd Street shut down on December 4, 1938."

article

• (informal, humorous, chiefly Internet slang) The (sometimes where "the" would not occur in normal English).
  ""[…] A sister of Joseph Gerard […] was found unconscious on the kitchen floor by the family cook early this morning. […]" […] What leads could they have, if the old lady was el zonko?"

name

• (transport, slang) Any one of several specific elevated railways.
  "The Washington Street El was torn down in 1987."

name

• (Java programming language) Initialism of Expression Language.