What does CADR stand for?

This acronym represents measurement for air purifiers. CADR stands for Clean Air Delivery Rate.
This measurement was developed by the Association of Home Appliance Manufacturers. It indicates the volume of filtered air delivered by an air purifier.
It is given in three measurements. One for pollen, one for tobacco smoke, and one for dust. The higher the CADR number, the faster the unit filters the air for that particular particle