FIFTH WHEEL


Meaning of FIFTH WHEEL in English

1. a horizontal ring or segment of a ring, consisting of two bands that slide on each other, placed above the front axle of a carriage and designed to support the forepart of the body while allowing it to turn freely in a horizontal plane.

2. a similar device used as a coupling to connect a semitrailer to a tractor.

3. a similar coupling between a heavy-duty pickup truck and a camping trailer (fifth-wheel trailer) that extends over the bed of the truck.

4. an extra wheel for a four-wheeled vehicle.

5. a superfluous, unneeded, or unwanted person or thing: They enjoy making any outsider feel like a fifth wheel.

[ 1870-75 ]

Random House Webster's Unabridged English dictionary.      Полный английский словарь Вебстер - Random House .