Comparative evidence

ku̯ath₂

• OInd. kvath- 'boil' (Whitney 1885: 27); 'prepare by heat'; 'digest'; 'be hot' (as the heart) (MW: 324)

References

MW = Monier-Williams, M. 1899. A Sanskrit-English Dictionary. Clarendon Press.
Whitney 1885 = Whitney W. D. 1885. The roots, verb forms and primary derivatives of the Sanskrit language. A supplement to his Sanskrit grammar. Leipzig.