六論

The six 外道論 vedāṇgas, works which are 'regarded as auxiliary to and even in some sense as part of the Veda, their object being to secure the proper pronunciation and correctness of the text and the right employment of the Mantras of sacrifice as taught in the Brāhmaṇas '. M. W. They are spoken of together as the 四皮陀六論 four Vedas and six śāstras, and the six are Sikṣā, Chandas, Vyākarana, Nirukta, Jyotiṣa, and Kalpa.