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 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

The cause of the accident was narrowed down to a cotter pin, which one of the mechanics at Valbuena Field had forgotten to replace after greasing the landing wheels that morning.

From Time Magazine Archive

Theirs is a world in which every boy matures to master small motors, to understand the importance of the cotter pin.

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

By lightly tapping in the taper cotter pin little by little, sufficient pressure is put on the cutter to make it an easy matter to completely re-face an old seat or form a new one.

From Gas and Oil Engines, Simply Explained An Elementary Instruction Book for Amateurs and Engine Attendants by Runciman, Walter C.