Allen bolt


Al·​len bolt ˈa-lən- How to pronounce Allen bolt (audio)
: a bolt with a hexagonal socket in its head that is designed to be used with an Allen wrench
The Allen bolt is integral to the crank and remains in it when the crank is removed from the spindle.Eugene A. Sloane, Sloane's New Bicycle Maintenance Manual, 1981

Word History


Allen Manufacturing Co., Hartford, Connecticut

First Known Use

1972, in the meaning defined above

Time Traveler
The first known use of Allen bolt was in 1972

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Dictionary Entries Near Allen bolt

Cite this Entry

“Allen bolt.” Dictionary, Merriam-Webster, Accessed 28 May. 2024.

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