turiya, visuddha-sattva, 'sankarsana' nama
tinho yanra amsa, sei nityananda-rama
turiya—transcendental; visuddha-sattva—pure existence; sankarsana nama—named Sankarsana; tinho yanra amsa—of whom that Sankarsana is also a partial expansion; sei nityananda-rama—that person is known as Balarama or Nityananda.
That Sankarsana, who is transcendental pure goodness, is a partial expansion of Nityananda Balarama.
Link to this page: https://prabhupadabooks.com/cc/adi/5/48