- 1A metal pin used to fasten two parts of a mechanism together.More example sentences
- She slid the cotter pin back through the nut and bolt and screwed the grease cap back on.
- A cotter pin acts a safety measure to prevent the arm from sliding off the stub.
- The cotter pin missed the male spline on the flap motor.
mid 17th century: of unknown origin.
More definitions of cotter pinDefinition of cotter pin in:
- The US English dictionary