[a. F. bouchon plug.] A cylindrical brass plug, tubular at the ends, to be inserted in the plate of a watch when the bearings are considerably worn. (The bouchon is a patent article of French manufacture: the English means of effecting the same purpose is called BUSHING.)
1884. F. Britten, Watch & Clockm., 35. A bouchon is selected as small as the pivot will admit.
