Banned Refrigerant is a term used to describe a type of refrigerant that has been phased out due to its negative environmental impact. The most common example of this is Freon, which is a chlorofluorocarbon (CFC) that was widely used in air conditioning and refrigeration systems until it was banned in the 1990s. Freon is a five-letter word that is often used as a crossword solution for the term Banned Refrigerant.