Old English hænep "hemp, cannabis sativa," from Proto-Germanic *hanapiz (cognates: Old Saxon hanap, Old Norse hampr, Old High German hanaf, German Hanf), probably a very early Germanic borrowing of the same Scythian word that became Greek kannabis (see cannabis). As the name of the fiber made from the plant, by c.1300. Slang sense of "marijuana" dates from 1940s; though scientific use for the narcotic derived from hemp dates to 1870.