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Medical Dictionary


noun semi·mem·bra·no·sus \ˌsem-ē-ˌmem-brə-ˈnō-səs\

Medical Definition of semimembranosus



  1. :  a large muscle of the inner part and back of the thigh that arises by a thick tendon from the back part of the tuberosity of the ischium, is inserted into the medial condyle of the tibia, and acts to flex the leg and rotate it medially and to extend the thigh

Illustration of semimembranosus

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