'nauseous' originates from Latin, specifically the word 'nauseosus,' where 'nausea' meant 'seasickness.'

'nauseosus' transformed into the Old French word 'nauseux,' and eventually became the modern English word 'nauseous' through Middle English.

Initially, it meant 'seasick,' but over time it evolved into its current meaning of 'feeling inclined to vomit or causing disgust.'