pereon
noun
pe·re·on pə-ˈrē-ˌän 
variants or pereion
pə-ˈrī-ˌän
: the thorax or the seven metameres comprising the thorax of some crustaceans (such as a decapod)
Word History
Etymology
New Latin, from Greek peraiōn, present participle of peraioun to transport, from peraios situated beyond, from pera beyond; akin to Greek poros passage — more at fare
First Known Use
1855, in the meaning defined above