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Medical Dictionary


noun mal·le·o·lus \mə-ˈlē-ə-ləs\

Medical Definition of malleolus

plural malleoli \-ˌlī\play

  1. :  an expanded projection or process at the distal end of the fibula or tibia at the level of the ankle:a:  the expanded lower end of the fibula situated on the lateral side of the leg at the ankle—called also external malleolus, lateral malleolusb:  a strong pyramid-shaped process of the tibia that projects distally on the medial side of its lower end at the ankle—called also internal malleolus, medial malleolusc:  a small projection of the tibia on the posterior side of its lower end at the ankle—called also posterior malleolus

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a timid, meek, or unassertive person

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