(golf) a set of numbered clubs with metal heads having various lofts (slopes of the faces); specifically, the number 2 iron with little loft for hitting the ballrelatively long distances, the number 5 iron with mediumloft and the number 9 iron with much loft for hitting the ballrelativelyshort distances. See also golf in this glossary.—AcademyLevel 0 Glossary Approved 3-12-90