1640, "to feel sick, to become affected with nausea," from pp. stem of L. nauseare, see nausea. In its early life it also had transitive senses of "to reject (food, etc.) with a feeling of nausea" (1646) and "to create a loathing in" (1654). Careful writers use nauseated
for "sick at the stomach" and reserve nauseous (q.v.) for "sickening to contemplate."