John Jeffery means in slang: John Jefferey is a rare name that refers to men with a great smile. Although you might think he has no imperfections, it’s a super legitimate and uncommon name. However, John Jefferey can be moody, shy and sometimes moody. Although they are attractive, their academic abilities can be uncanny. They don’t seem like bookworms and have a remarkable ability to stay focused on work. They can be irritatingly vain. (in Slang Dictionary, added by Lorenzo Trujillo)