sa vai bako nāma mahān
āgatya sahasā kṛṣṇaṁ
tīkṣṇa-tuṇḍo ’grasad balī
saḥ—that creature; vai—indeed; bakaḥ nāma—by the name Bakāsura; mahān asuraḥ—a great, gigantic demon; baka-rūpa-dhṛk—assumed the bodily shape of a big duck; āgatya—coming there; sahasā—all of a sudden; kṛṣṇam—Kṛṣṇa; tīkṣṇa-tuṇḍaḥ—sharp beak; agrasat—swallowed; balī—very powerful.
That great-bodied demon was named Bakāsura. He had assumed the body of a duck with a very sharp beak. Having come there, he immediately swallowed Kṛṣṇa.
Link to this page: https://prabhupadabooks.com/sb/10/11/48