the term “Śodhana”: means “cleansing”, “purification”. It”s a Prāṇāyāma technique that cleans the subtle channels “Nāḍī” and nervous system with a kind of alternate respiration. In Aṣṭāṅgayoga (Yoga Korunta), it corresponds with the name of the second series (intermediate series) meaning “Purification of the nervous system”.
Nāḍī Śodhana
the term "Śodhana": means "cleansing", "purification".