Vach means Speech. In the Rig Ved, Vach appears to be the personification of speech by whom knowledge was communicated to man - Uvaach.

Thus she is said to have entered the Rishi, and to make whom she loves terrible and intelligent.

She was generated by the gods, and is called the Divine Vaach, queen of the gods, and she is described as the melodious cow who milked forth sustenance and water, who yields us nourishment and sustenance. The Braahman associate her with Prajaapati in the work of creation.

In the Taittireeya Braahman she is called the mother of the Ved, and the wife of Indra, who contains within herself all the worlds.

In the Shatapath Braahman she is represented as entering into a sexual relationship with Prajaapati, who, being desirous of creating, connected himself with various spouses, and among them, through his mind, with Vach, from whom he created the waters.

In the Kath Upanishad this idea is more distinctly formulated :- Prajaapati was this universe. Vaach was a second to him. He associated sexually with her; she became pregnant; she departed from him; she produced these creatures; she again entered into Prajapati.

The Aitareya Braahman and the Saatapath Braahman have a story of the Gandharv having stolen the Som juice, or, as one calls it, King Som, and that as the Gandharv were fond of women, Vaach was, at her own suggestion, turned into a female by the gods and Rishi, and went to recover it from them.

In the Atharv Ved she is identified with Viraj, and is the daughter of Kaam Dev (desire). That daughter of thine, O Kaam, is called the cow, she whom sages denominate Vaach-Viraaj.

The Mahaabhaarat also calls her the mother of the Ved, and, says, "A voice derived from Brahm entered into the ears of them all; the celestial Saraswatee was then produced from the Heavens.

Here and in the later mythology, Saraswatee was identified with Vaach, and became under different names the spouse of Brahmaa and the goddess of wisdom and eloquence, and is invoked as a muse, generally under the name of Saraswatee, but sometimes as Vaach too.

The Bhaagvat Puraan recognizes her as the blender and enchanting daughter of Brahmaa, for whom he had a passion, and from whom mankind was produced, that is the female Viraaj. Saraswatee, as wife of Brahma and goddess of wisdom, represents perhaps the union of power and intelligence which was supposed to operate in the work of creation.

According to the Padm Puraan, Vaach was the daughter of Daksh, one of the wives of Kashyap, and mother of the Gandharv and Apsaraa.

Our priests during all auspicious functions recite the Mantra "Namo vaachaspatim". Probably he may be referring Vaach as the Saraswatee and pray for correct pronunciation.