leitmotiv
noun [ C ] literature, music, art specialized (also leitmotif) uk/ˈlaɪt.məʊ.tiːf/ us/ˈlaɪt.moʊ.t̬iːf/
（指艺术、文学或尤指音乐作品中反复出现的）主题，中心思想，主旋律
a phrase or other feature that is repeated often in a work of art, literature, or music and that tells you something important about it
Death and renewal are leitmotivs running through the whole novel. 死亡与新生是贯穿这部小说的主题。