metasoma
/ˌmɛtəˈsəʊmə/Zoology
noun
The posterior section of the body in various invertebrates that have a body divided into two or three distinct sections (e.g. arachnids, cephalopods, hemichordates, lophophorates, etc.); (Entomology ) the broad or swollen part of the abdomen behind the petiole of many hymenoptera.
Origin
Late 19th century; earliest use found in Henry Nicholson (1844–1899), biologist and geologist. From meta- + ancient Greek σῶμα.