In music, a contrapuntal form with two or more subjects (principal melodies) for a number of parts, which enter in succession in direct imitation of each other or transposed to a higher or lower key, and may be combined in augmented form (larger note values). It represents the highest form of contrapuntal ingenuity in works such as J S Bach’s Das musikalische Opfer/The Musical Offering 1747, on a theme of Frederick II of Prussia, and Die Kunst der Fuge/The Art of the Fugue published 1751, and Beethoven’s Grosse Fuge/Great Fugue for string quartet 1825–26.
A musical form consisting of a theme repeated a fifth above or a fourth below its first statement.

ETYM French, from Italian fuga, from Latin fuga a fleeing, flight, akin to fugere to fiee. Related to Fugitive.
In psychology, an abnormal state in which a person under emotional stress suddenly leaves home, apparently forgetting everything about his or her normal life, and assumes a new identity. The state is usually temporary and is probably due to repression.
A dreamlike state of altered consciousness that may last for hours or days.