cotter-pin

n (engineering 工) pin used to hold parts of machinery in place 开尾销; 扁销.

costliness, costly, costume, costume jewellery, costumier, cosy, cosy (US cozy), cot, cot-death, cotangent, cote, coterie, coterminous, cottage, cottage cheese, cottage hospital, cottage industry, cottage loaf, cottage pie, cottager, cotton, cotton candy, cotton seed oil, cotton wool, cotton-wool, cottontail, cotyledon, couch, couch-grass, couchant, couchette, cougar, cough, could, coulter (US colter), council, council estate, council flat, council house, council house, council-chamber,