leitmotiv

/L AY1 T M OW0 T IY0 V/
noun
  1. 1

    A melodic theme associated with a particular character, place, thing or idea in an opera.

  2. 2

    A recurring theme.

Source: https://en.wiktionary.org/wiki/leitmotif, https://en.wiktionary.org/wiki/leitmotiv