Complex sentence: One is the style of a prayer service (Ashkenaz, Sephardi, Nusach Sefard or Nusach Ari); another is the melody of the service depending on when the service is being conducted.
Split into simpler sentences: One is the style of a prayer service (Ashkenaz, Sephardi, Nusach Sefard or Nusach Ari). Another meaning of the word is the melody of the service depending on when the service is being conducted.