Injunction derives, via Anglo-French and Late Latin, from the Latin verb injungere, which in turn is based on jungere, meaning "to join." Like our verb enjoin, injungere means "to direct or impose by authoritative order or with urgent admonition." (Not surprisingly, enjoin is also a descendant of injungere.) Injunction has been around in English since at least the 15th century, when it began life as a word meaning "authoritative command." In the 16th century, it developed a legal second sense applying to a court order. It has also been used as a synonym of conjunction, another jungere descendant meaning "union," but that sense is extremely rare.