fifth wheel

Primary Meanings of fifth wheel

1.
n
someone or something that is unwanted and unneeded
2.
n
a steering bearing that enables the front axle of a horse-drawn wagon to rotate
3.
n
an extra car wheel and tire for a four-wheel vehicle
Full Definitions of fifth wheel
1

n someone or something that is unwanted and unneeded

Synonyms:
deadwood
Type of:
redundance, redundancy
the attribute of being superfluous and unneeded
2

n a steering bearing that enables the front axle of a horse-drawn wagon to rotate

Type of:
bearing
a rotating support placed between moving parts to allow them to move easily
3

n an extra car wheel and tire for a four-wheel vehicle

Synonyms:
spare
Type of:
car wheel
a wheel that has a tire and rim and hubcap; used to propel the car

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