cotter pin
noun Machinery.
a cotter having a split end that is spread after being pushed through a hole to prevent it from working loose.
Origin of cotter pin
First recorded in 1890–95
Words nearby cotter pin
cottager,
cottaging,
cottbus,
cotte's operation,
cotter,
cotter pin,
cotter slot,
cottian alps,
cottid,
cottier,
cotton
British Dictionary definitions for cotter pin
cotter pin
noun machinery
a split pin secured, after passing through holes in the parts to be attached, by spreading the ends
a tapered pin threaded at the smaller end and secured by a nut after insertion