SLIDE RULE

a device for performing mathematical calculations, consisting essentially of a ruler having a sliding piece moving along it, both marked with graduated scales: now largely replaced by the electronic calculator. —The Evolution of a Science Glossary Final Approval early March 1990

an instrument for quick figuring made up of a ruler with a central sliding piece, both marked with scales.a device for performing mathematical calculations, consisting essentially of a ruler having a sliding piece moving along it, both marked with graduated scales now largely replaced by the electronic calculator.