fer‧rule /ˈferuːl, ˈferəl $ ˈferəl/
noun [countable] technical[
Date: 1600-1700;
Origin: verrel (15-19 centuries) (influenced by Latin ferrum 'iron'), from Latin viriola 'small band worn around the arm']
a piece of metal or rubber put on the end of a stick to make it stronger
[TahlilGaran] Dictionary of Contemporary English ▲