nikasaḥ is an alternate of nikaṣaḥ. 1 A touch-stone, whet-stone; nikaṣe hemarekheva R. 17. 46; Mv. 1. 4.

2 (Fig.) Anything serving as a touch-stone, a test; na- nveṣa darpanikaṣastava caṃdraketuḥ U. 5. 10; ādarśaḥ śikṣitānāṃ sucaritanikaṣaḥ Mk. 1. 48; Dk. 1; K. 44.

3 A streak or line of gold made on a touch-stone; kanakanikaṣaruciśucivasanena śvasiti ma sā parijanahasanena Gīt. 7; kanakanikaṣa- snigdhā...