Lost

Lost could mean:
 Lost, mislaid, and abandoned property
 Lost, Aberdeenshire, a tiny hamlet in Scotland
 Lost Energy, a commercial energy drink
 Mustard gas, from LOmmel and STeinkopf who developed a process for mass-producing the gas for war
 Local Option Sales Tax (LOST), a special-purpose tax often appended to standard state sales tax on certain purchases

In entertainment:
 Lost (TV series), a drama which follows the lives of plane crash survivors who land on a mysterious island
 Lost (video game), a video game based on the television series
 Lost (2001 TV series), a short-lived reality television program
 Lost (1956 movie), a British thriller directed by Guy Green
 Lost (2004 movie), an American indie thriller starring Dean Cain
 Lost (2001 novel), a revisionist novel by Gregory Maguire
 The Lost, a 2006 memoir by Daniel Mendelsohn
 Lost (Eightball album), a 1998 album by American rapper Eightball
 Lost (RTZ album), a 1999 album by American rock band RTZ
 Lost (Cool Calm Pete album), a 2005 album by American hip hop artist Cool Calm Pete
 "Lost" (Kreator song), a 1995 single by the German thrash metal band Kreator
 "Lost" (song), a 2003 single by English singer Skin