Petiole (insect anatomy) a pedicel, but in entomology, that term is more correctly reserved for the second segment of the antenna; while in arachnology, 'pedicel' is the accepted term to define the constriction between the cephalothorax and abdomen of spiders. The plump portion of the abdomen posterior to the petiole (and postpetiole in the Myrmicinae) is called the gaster. The structure of the petiole is an easy way to visually classify ants, because the major subfamilies of Formicidae have structural differences: some ants have two-segmented petioles, while others have a single-segmented petiole. Petiole may also be used in the context of wing veins,
Insect term also form the usual word for "insect" in Welsh (, from ' "to cut" and " mil", "animal"), Serbo-Croatian ("zareznik", from "rezati", "to cut"), Russian ( "nasekomoje", from "seč'/-sekat"', "to cut"), etc. The precise definition of the taxon Insecta and the equivalent English name "insect" varies; three alternative definitions are shown in the table. In the broadest circumscription, Insecta "sensu lato" consists of all hexapods. Traditionally, insects defined in this way were divided into "Apterygota" (the first five groups in the table) – the wingless insects – and Pterygota – the winged insects. However, modern phylogenetic studies have shown