Wagon wheel, with forged linchpin
A modern linchpin with an integral spring retainer

A linchpin, also spelled linch pin, lynchpin, or lynch pin, is a fastener used to prevent a wheel or other part from sliding off the axle upon which it is riding. The word is first attested in the late 14th century and derives from Middle English elements meaning "axletree pin".[1][2]

Securing implements onto the three-point hitch of a tractor is an example of application. Linchpins may also be used in place of an R-clip for securing hitch pins.[citation needed]

The word "linchpin" is also used figuratively to mean "something [or someone] that holds the various elements of a complicated structure together".[3]

See alsoEdit


  1. ^ "linch-pin, n.". OED Online. June 2014. Oxford University Press. (accessed August 25, 2014; now behind paywall).
  2. ^ "linchpin (n.)". Online Etymology Dictionary. (accessed June 01, 2018).
  3. ^ "Linchpin". Retrieved 2012-03-24.