4 Definitions

A future event or problem that exists outside of the control of the project that will have an adverse impact on the project if it occurs. Risk involves the probability of occurrence and the possible consequences or impact. Unlike an issue that is a current problem that must be dealt with, a risk is a potential problem that has not yet occurred.
defined by PCoE Oregon .Gov
A measure of the probability and severity of undesired effects. Often taken as the simple product of probability and consequence
defined by 6SixSigSigma
Potential impact that indicates the possibility of loss, injury, disadvantage, or destruction
See Business Risk