Before revision: A jibAmerican Heritage Dictionary or jib arm is the horizontal or near-horizontal beam used in many types of crane to support the load clear of the main support.James T. Frane Craftsman's Illustrated Dictionary of Construction Terms 1572180080 1994 p83 "crane jib -an extension at the top of a crane tower that gives the crane additional lifting or moving capabilities.
After revision: A jib or jib arm is the horizontal or near-horizontal beam used in many types of crane to support the load clear of the main support.James T. Frane Craftsman's Illustrated Dictionary of Construction Terms 1572180080 1994 p83 "crane jib -an extension at the top of a crane tower that gives the crane additional lifting or moving capabilities.