gastrocnemius
Concise Oxford English Dictionary © 2008 Oxford University Press:
gastrocnemius /ˌgastrə(ʊ)ˈkniːmɪəs/ (also gastrocnemius muscle)
▶noun (pl. gastrocnemii /-mɪʌɪ/) Anatomy the chief muscle of the calf of the leg, which flexes the knee and foot.
– origin C17: mod. L., from Gk gastroknēmia ‘calf of the leg’, from gaster, gastr- ‘stomach’ + knēmē ‘leg’ (from the bulging shape of the calf).
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