Strait jacket definition of strait jacket in the free online encyclopedia A plastic housing trueoutletjeans that contains a floppy disk.Any exterior covering or casing, such as the insulating cover of a boiler (Nucleonics)A thin container for one or more fuel slugs, used to prevent the fuel from escaping into the coolant of a Cheap True Religion Jeans reactor.Also known as can;Cartridge. (Ordnance)Cylinder of steel covering and strengthening the breech end of a gun or howitzer http://www.pdu-direct.com/ tube. The water jacket on some machine guns. (Petroleum engineering)The support structure of a steel offshore production platform;It is fixed to the seabed by piling, and the superstructure is mounted on it. Jacket, 1 1.A metal or cloth covering over the heat insulation which is applied to exposed heating pipes and ducts. 2.An outer casing around a pipe or vessel, the space between being filled with a fluid for cooling, heating, or maintaining a fixed temperature. Jacket a covering, usually removable, of a book or booklet in the form of a sheet with flaps.It is generally made of heavy paper coated for purposes of reinforcement or covered with a transparent synthetic film that also improves the jacket appearance.Jackets are sometimes made from polymer films.Originally, jackets were used to protect the bindings of expensive editions from damage;They were later used for purposes of publicity as well.The jacket sometimes serves a purely aesthetic purpose.