The long-sleeved garment used to bind a person’s arms tightly against the body is a straitjacket. The spelling derives from a little-used, mostly archaic definition of strait—i.e., tightly fitting. The word is commonly misspelled in a number of ways, including straightjacket, strait-jacket, straight-jacket, strait jacket, and straight jacket.
Examples
Yet businessmen and victims say supplies are being held up as bureaucracies fall back on tired old rules and straitjacket procedures. [The Economist]
In the dark ages, I was pinioned in the straitjacket of train timetables from East Croydon and West Dulwich in London. [Financial Times]
They also agreed to allow the fund to buy bonds directly from governments in need of finance, although only within the straitjacket of a bailout. [Sydney Morning Herald]