What is a bioretention pond, bioretention cell, bioretention basin, or rain garden?

Bioretention ponds, bioretention cells, and bioretention basins are common names referring the same systems.  Rain gardens are usually smaller versions of these systems.  The idea is to capture stormwater runoff, specifically the water from smaller, more frequent events.  Generally, this water contains the most contaminants of nutrients, oils/grease, and other debris.  The bioretention areas are landscaped with plants and contain engineered soil to help filter the runoff and reduce the quantity of the runoff.  A bioretention pond is designed to slowly release clean water back into the watershed over a longer period of time that benefits the environment.