HIGHBALL

a railroad signal meaning "go ahead." From the early railroad signal device consisting of a large white ball hung from a pole. The ball was lowered to indicate "stop" and raised to show that the way was clear ahead. —PDC Volume 1 Approved Glossary

a railroad signal meaning "go ahead." From the early railroad signal device consisting of a large white ball hung from a pole. The ball was lowered to indicate "stop" and raised to show that the way was clear ahead.