The origin of queasy is uncertain - according to the OED, a possibility is that it is a borrowing from early Scandinavian, cf. Old Icelandic kveisa "boil" and Norwegian Nynorsk kveis "hangover". These words might be from PIE *gʷeiH- "to prevail, be mighty" ("to press down, conquer" in the AHD). Cf. Old English cwysan "to crush".
*gʷeiH- is the source of Sanskrit ji "conquer, overcome" and जिन jina, "victor", a Buddha. From this comes the word जैन jaina "a worshiper of the Jinas" and Jain. The Sanskrit is also the source of Hindi जय jay "victory" as in Jai Ho.