'gaseous' originates from the Latin word 'gas,' which was coined by the Flemish chemist Jan Baptist van Helmont in the 17th century.

'gas' was introduced into English from the Latin word 'gas,' and eventually became the modern English word 'gaseous' with the addition of the suffix '-ous.'

Initially, it referred to any form of air or vapor, but over time it evolved into its current meaning of 'in a gaseous state.'