cotter pin definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a split pin used as a cotter, fastened in place by spreading apart its ends after it is inserted
cotter pin definition by American Heritage Dictionary
A split cotter inserted through holes in two or more pieces and bent at the ends to fasten the pieces together.