A relief valve set to open at a pressure below that at which a container (such as a boiler) would burst.
Any mechanism offering relief from pressure or tension, e.g. emotionally.
A United States law, codified at 18 USC §3553(f), authorizing a judge to disregard mandatory minimum sentences for some criminals with few or no prior offenses.
A type of electron tube that controls electron current through vacuum between electrodes within a sealed container, usually of glass or metal and often designed to be easily installed in and removed from the equipment in which it is used.