Sideburns are the strips of hair a man grows down in front of his ears, on the sides of the face. They are not a beard (that is the chin and jaw) and not a moustache (that is the lip). Some people wear them short and neat; some let them get wide and bushy. The look comes and goes with fashion. The name is a twist on a real person: an American general, Ambrose Burnside, was famous for thick hair just there. People called that style burnsides, and then the two halves of the name swapped round — sideburns. So the burn here is not fire; it is half of a surname. The word is almost always plural.

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