cotter pin

American  

noun

Machinery.

1. a cotter having a split end that is spread after being pushed through a hole to prevent it from working loose.

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cotter pin British  

noun

1. a split pin secured, after passing through holes in the parts to be attached, by spreading the ends

2. a tapered pin threaded at the smaller end and secured by a nut after insertion

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Etymology

Origin of cotter pin

First recorded in 1890–95

Example Sentences

At Tsurumi, outside Yokohama, another cotter pin evidently sheared off the wheel housing of a southbound freight car.

From Time Magazine Archive

At the Mikawa mine on southern Kyushu island, a cotter pin apparently fell out of a coupling on a string of coal cars halted on a slight incline.

From Time Magazine Archive

As the U.S. cotter pin in the United Nations, Lodge was given Cabinet status and a large voice in U.S. policy�and grew in stature to measure up to both.

From Time Magazine Archive

Serial writers ran out of hazards years ago, have been working switches on them ever since; the loose cotter pin on the stagecoach, for example, has been used an estimated 7,000 times.

From Time Magazine Archive

This will allow 3/4 in. of the iron rod to project from the bottom edge of the metal through which a hole is drilled for a cotter pin.

From The Boy Mechanic: Volume 1 700 Things for Boys to Do by Popular Mechanics Co.