'downdraught' originates from the combination of 'down' and 'draught', where 'down' meant 'toward a lower place' and 'draught' referred to 'a current of air'.

'draught' changed from the Old English word 'dræht' and eventually became the modern English word 'draught'.

Initially, it meant 'a current of air moving downward', and this meaning has largely remained the same in modern usage.