n.
Pronunciation: ' tho ̇ r- ˌ aks
Function: noun
Inflected Form: plural tho · rax · es or tho · ra · ces \ ' tho ̇ r- ə - ˌ s ē z \
Etymology: Middle English, from Latin thorac-, thorax breastplate, thorax, from Greek th ō rak-, th ō rax
Date: 15th century
1 : the part of the mammalian body between the neck and the abdomen also : its cavity in which the heart and lungs lie
2 : the middle of the three chief divisions of the body of an insect also : the corresponding part of a crustacean or an arachnid