Plural of airer; devices or people that air things out, or frames for drying clothes in the air.
From Middle English 'airen' (to expose to air), from Old English 'ærest.' The suffix '-er' denotes an agent or device that performs the action of airing.
Clotheslines and drying racks were once called airers because they literally made clothes 'airier'—the Victorians had whole collapsible wooden airers that folded away, ancestors of today's drying racks.
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