means The unsettled, faintly nauseated feeling in your stomach, or a more general sense of unease and squeamish discomfort.

from From 'queasy,' which surfaced in late Middle English to describe unsettled stomachs and unsettling situations alike. Its deeper roots are murky — etymologists honestly shrug here — though it's often linked to Old French 'coisier' (to hurt, wound) or possibly an Old Norse source like 'kveisa,' a boil or sore. Either way, the word has spent centuries meaning exactly what it sounds like: a little ill, a little queer in the belly.