Most people in a current generation might believe this is the proprietary name of an internet services provider. They are, of course, absolutely right and some ot them will not be surprised to learn that the word first entered the language in the early 18th century. It was coined by Jonathan Swift in his novel Gulliver’s Travels (1726) in which he names a race of brutish, humanoid creatures as yahoos. As such, the word then passed into the language to describe persons or their behaviour as uncultured, bestial and antisocial. See also Yob.