This adjective is used for goddess Saraswati. It means - bowed by the king of gods, Lord Indra. This adjective is used to indicate the glory of goddess Saraswati. However, Indra himself is full of divinity and now he has no desire to attain anythingh. Still he worships her, because he knows about her importance. If the king of gods, Indra accepts the glory of goddess Saraswati, we should also accept it. We should worship her for the attainment of knoweldge.