blackball

    To "blackball" someone" is to refuse him membership in a club.  An old-fashioned gentlemen's club had a vote on whether or not to accept a new applicant as a member. Each person had a white ball and a black ball. The voting was accomplished by depositing either the white ball, for yes, or the black ball, for no, in a container of some kind. In some clubs one black ball meant membership would be denied. In some clubs it was three black balls. So one person could "blackball" a prospective applicant for membership.