vapour
UK: ˈveɪpə | US: ˈveɪpər
n. a visible suspension of fine particles of a liquid or solid in air or another gas
n. (archaic) a substance diffused or suspended in the air, especially one normally liquid or solid
v. (rare) to emit or become vapor
vapour = vap<steam> + our<noun suffix>
- vap (from Latin vapor meaning "steam, heat, exhalation")
- our (a noun-forming suffix of Latin origin, often indicating a state or condition)
Etymology Origin:
The word "vapour" traces back to Latin vapor, which referred to steam or exhalation, often linked to heat or evaporation. It entered Middle English via Old French vapour, retaining its core meaning of a gaseous or misty substance. The suffix -our (later simplified to -or in American English) was a common Latin-derived ending in Old French, used to form nouns describing states or qualities. Over time, "vapour" narrowed to specifically describe visible gaseous suspensions, though archaic uses included broader atmospheric phenomena.
The kettle released a cloud of vapour as it boiled.
Morning fog is essentially vapour condensed near the ground.
In medieval medicine, "vapours" were thought to cause melancholy.
The chemist studied the behaviour of vapour under pressure.
His breath formed vapour in the cold winter air.