A chaise longue is an upholstered sofa in the shape of a chair that is long enough to support the legs.

In modern French the term chaise longue can refer to any long reclining chair such as a deckchair. A literal translation in English is “long chair”. In the United States the term lounge chair is also used to refer to any long reclining chair. In the United States, chaise longue is nearly always written “chaise lounge” and pronounced /ˌtʃeɪsˈlaʊndʒ/, the first constituent a spelling pronunciation, the second a 19th-century folk-anagrammatic adaptation of French longue.

The chaise longue has traditionally been associated with psychoanalysis and many psychoanalysts continue to keep chaises longues in their offices for use in psychotherapy.