ExpertGlossary

When a bond isn't backed by collateral or security of some kind, such as a mortgage, that can be used to repay the bondholders if the bond issuer defaults, the bond is described as unsecured.

However, most unsecured bonds pose limited risk of default, since the companies that issue them are usually financially sound. Unsecured bonds are also known as debentures.

In meteorological use: A colloquial term used to describe a condition in the atmosphere conducive to precipitation. This term typically is associated with the passage of surface or upper level low pressure systems, fronts or other phenomenon when precipitation expected.

In solar-terrestrial use: With regard to geomagnetic levels, a descriptive word specifically meaning that 8 is less than or equal to the Ap Index which is less than or equal to 15.