From Longman Dictionary of Contemporary Englishfibulafib‧u‧la /ˈfɪbjələ/ noun [countable] medical HBHthe outer bone of the two bones in your leg below your knee
Examples from the Corpus
fibula• Now he is facing his toughest fight yet - back to fitness after suffering a fractured fibula and damaged ankle ligaments.• Blood had congealed thickly on the end of the smashed fibula.Origin fibula (1500-1600) Latin “piece of jewelry for fastening clothes” (because of the shape of the two bones) 