[1] : The Collaborative International Dictionary of English v.0.48

gastrocnemius \gas`trocne"mius\, n. nl., from gr. ? the calf
   of the leg. anat.
   the muscle which makes the greater part of the calf of the
   leg.
   1913 webster

[2] : WordNet (r) 2.0

gastrocnemius
     n : the muscle in the back part of the leg that forms the
         greater part of the calf; responsible for the plantar
         flexion of the foot syn: gastrocnemius muscle
see also:
gastrocnemius muscle 

Gastrocnemius >> G Words
Gastrocnemius, definition of term: Gastrocnemius
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