Why does the term jack-o’-lantern have a man’s name -- “Jack?” Merriam-Webster’s online dictionary gives one explanation. It says people in England began using the term in the 17th-century. It meant “a man with a lantern” or a night watchman. At that time, people living in England reportedly called a man they did not know “Jack.” So, an unknown man carrying a lantern was sometimes called "Jack with the lantern" or "Jack of the lantern."