an air stream across a doorway to exclude draughts, etc
air curtain in American English
or air door
a downward draft of air at an open doorway for maintaining even temperatures within a building
air curtain in American English
noun
compressed air directed, usually downward, across a doorway so as to form a shield to exclude drafts, insects, etc
Examples of 'air curtain' in a sentence
air curtain
The worst offenders are those with 'air curtains': fan-powered devices that maintain the store's temperature despite its doors being open to the elements outside.