What is the origin of 'sleep tight'?
Read moreOne of the mysteries of the English language finally explained.

(Frequently in military contexts) an act of determinedly holding or defending a position against a (more powerful) opposing force; a final show of resistance or protest; especially in "to make one's (also a) last stand".
Mid 17th century; earliest use found in John Trapp (1601–1669), Church of England clergyman and writer on theology.