Importer of Record (IOR): An authorized person or entity that takes responsibility for an import. (e.g. the person or business putting their name on the shipping paperwork as the consignee or importer.) This is typically also the party that is responsible for completing the necessary documentation and paperwork for the shipment to clear customs.
Another common definition in the logistics industry is: the person or entity putting their name or company name on the import paperwork
If you’re looking to have a more holistic understanding of what an IOR is, read more here.