'atmosphere' originates from Greek, specifically the word 'atmosphaira,' where 'atmos' meant 'vapor' and 'sphaira' meant 'sphere.'

'atmosphaira' transformed into the French word 'atmosphère,' and eventually became the modern English word 'atmosphere' through Middle English.

Initially, it meant 'vapor sphere,' but over time it evolved into its current meanings of 'gaseous envelope' and 'mood or tone.'