#heart.internal_organ__pump__ticker  the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions pump blood through the body; "he stood still, his heart thumping wildly"
  supertype:  internal_organ__viscus  a main organ that is situated inside the body
  part:  coronary_artery  cardiac_muscle  cardiac_valve  valve.anatomical_structure
  part of:  circulatory_system
  subtype:  athlete's_heart  enlarged heart commonly found among athletes trained for endurance
  subtype:  biauriculate_heart  a heart (as of mammals and birds and reptiles) have two auricles

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