https://definitions.uslegal.com/i/in-bond/

In Bond is a term applied to the status of merchandise admitted provisionally to a country without payment of duties. Imported goods are placed in warehouses approved by the customs authorities, and importers were to give bonds for payment of duties when the goods were removed. All goods deposited in a warehouse, without payment of duty on the first importation, upon being entered for home consumption, are chargeable with existing duties on like goods. While the goods are in the warehouse ("in bond") the owner may subject them to various processes necessary to fit them for the market, such as the repacking. The system of warehousing has proved of great advantage both to importers and purchasers, as the payment of duty is deferred until the goods are required.

https://thebrazilbusiness.com/article/bonded-warehouse-in-br...

https://www.charleskendall.com/uploads/files/countryguides-b...

Classification and the bonded warehouse
When goods arrive in Brazil, the carrier will deliver the required documentation to the consignee or their legalised representative who will issue the authority for transfer of the goods from the port/airport to the bonded warehouse. This procedure can take up to 48 hours. Once the **materials are in Bond**, a process of classification will commence.