Leitmotif

Originally a musical term, used to describe a device employed by composer Richard Wagner (German, 1813-1883). A specific musical phrase was associated with the first and each recurring appearance of a character, idea, or emotion. Then, by extension, a leitmotif came to have the general meaning of a recurring and often dominant theme in art, writing, or in life itself. Literally the German word means "leading or guiding motive."(pr. LI:T-moh-TEEF)