Comparative evidence

terǵʰ, sterǵʰ

• Hitt. istark- 'ail', 'afflict' (EDHIL: 416f.)

• Hitt. istarnink- 'ail', 'afflict' (EDHIL: 416f.) The etymology of these verbs is disputed. Besides the connection to Skt. tarh- 'crush' the Hittite verb was also compared to Lith. sergù 'be ill' (HED 1/2: 475ff.) or Lith. tersiù 'befoul' (EDHIL: 416f.)

References

EDHIL = Kloekhorst, A. 2008. Etymological Dictionary of the Hittite Inherited Lexicon. Brill.
HED = Puhvel, J. 1984 - . Hittite Etymological Dictionary. Mouton.