(1) a "proprietary interest" is something that a person owns. (2) "interest granted by way of security" [also called a "security interest"] means a right given to a creditor in a debtor's property to assure [legal term "to secure"] the payment of a debt. (A creditor is someone who is owed money. A debtor is someone who owes money.) If the debtor does not pay the debt, the creditor can "foreclose" on the property. This means that the creditor and debtor go through a legal process that allows the creditor to terminate the debtor's rights in the property, for example, by forcing a sale of the property so that the proceeds of the sale are paid to the creditor (3) "chargee" is another word for a creditor who has a security interest in a debtor's property.
To say all of this in a more simple way: It is a security interest that a creditor has in a debtor's property, and the creditor has the right to foreclose on the property in order to achieve the payment of the debt to him.