trilobite
/ˈtraɪləʊbaɪt/noun
1- a fossil marine arthropod that occurred abundantly during the Palaeozoic era, with a carapace over the forepart, and a segmented hindpart divided longitudinally into three lobes三叶虫。
1.1
- Subphylum Trilobita, phylum Arthropoda: numerous classes and orders.三叶虫亚门, 节肢动物门：众多纲和目。
词源
mid 19th cent.: from modern Latin Trilobites, from Greek tri- 'three' + lobos 'lobe'.