'airest' originates from the English word 'airy', which comes from the Old English word 'aerian', meaning 'to be light or breezy'.

'airy' evolved from the Old English 'aerian' and eventually became the modern English word 'airy', with 'airest' being its superlative form.

Initially, 'airy' meant 'to be light or breezy', and this meaning has largely remained the same in modern usage.