Securities such as bonds or notes supported by collateral assets are called Asset-Backed Securities. The assets are typically a group of illiquid assets that are unable to be sold individually. Pooling the assets into financial instruments allows them to be sold to general investors, a process called securitization, and allows the risk of investing in the underlying assets to be diversified because each security will represent a fraction of the total value of the diverse pool of underlying assets. The underlying assets can include common payments from credit cards, auto loans, and mortgage loans, to cash flow from leases, royalty payments and such other revenues.
The following is an example of a Federal Statute defining the term:
According to 12 CFR 12.2 [Title 12 -- Banks and Banking; Chapter I -- Comptroller of the Currency, Department of the Treasury; Part 12 -- Recordkeeping and Confirmation Requirements for Securities Transactions], asset-backed security means a security that is primarily serviced by the cashflows of a discrete pool of receivables or other financial assets, either fixed or revolving, that by their terms convert into cash within a finite time period plus any rights or other assets designed to assure the servicing or timely distribution of proceeds to the security holders.