Liability which is difficult to quantify, or which may or may not come to pass, such as an outstanding lawsuit.
An obligation that could occur at some time in the future caused by an event in the past. Wow, where does that get you? It is an incomplete event that needs to be identified in the financial statements of a company even though it may be difficult to quantify. An example of such a liability would be a pending lawsuit.
A potential liability that can develop into a real liability if a possible subsequent event occurs.