What is a “retarded potential”?

In Physics: The retarded potential is the vector or scalar potential at a distance very far away from a source of electromagnetic radiation.  Since radiated fields travel at the speed of light in vacuum, any change in the properties of the source must have time to propagate through space before they can affect objects located large distances away.  The time lapse that this requires is called “retarded time”, and this retarded time is used in the formulation of the retarded potentials.

In Society: The retarded potential is a judgmental and often exceedingly harsh measure of the intelligence of a person based on the inane and ill-thought-out gibberish that he or she posts online when trying to discuss the merits of a scientific article or principle.  It can be interpreted as the probability that an online commenter is retarded.