Brahmā Is Proud (English [summary]) in: South Asia — Tamil
This is the legend which explains this highly imaginative nomenclature. Brahmā, deluded by pride about his privileged status (as creator etc.), thought that he would be able, through his own effort, to obtain a vision in samādhi of Viṣṇu. All his attempts, however, failed; finally, he was advised to perform an aśvamedha sacrifice in the holy town Kāñcīpuram. Although invited to participate in this sacrifice, his wife Sarasvatī (herself busy with performing tapas in the river Sarasvatī) refused, because at the time she was quarrellin g with Brahmā. But when she came to know that Brahmā’s other wives were taking part in the sacrifice, she became jealous and rushed in the form of a river vegavatī “with great vehemence” towards the place where the aśvamedha was being performed, in order to sweep away its altar. “But he who is his father and has the serpent as his couch had compassion with the primordial Unborn (=Brahmā) and turned himself into a dam,” and thereby blocked the flow of the river.
– Hardy, Friedhelm, “Ideology and Cultural Contexts of the Śrīvaiṣṇava Temple,” The Indian Economic and Social History Review 14 (1977), pp. 119-151, p. 145. [This source is in the public domain; download here].
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