Comparative evidence

ksneu̯

• OInd. kṣṇu- 'whet' (Whitney 1885: 31); 'sharpen' (MW: 333)

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.