The diaphragm. The diaphragm.
It is called the border. There are border crossing set up on most of them to control who comes in or out of the country.
In a beetle the part of the body between the head and abdomen is called the thorax. The thorax contains important body structures.
Pharynx
In a beetle the part of the body between the head and abdomen is called the thorax. The thorax contains important body structures.
It is called a border.
The border line between India and Nepal is called the India-Nepal border or the Indo-Nepal border.
An abdomen
The Border between the two countries separating Russia and China is just that a Border line.
The boarder between two plates is called a boundary.
It is simply called the England/Wales border but it does roughly follow the line of Offa's Dyke, which is an ancient earthwork which once marked the border between King Offa's kingdom and Wales.
The border line between Myanmar and Bangladesh is called the India-Myanmar-Thailand Trilateral Highway. The border line between Myanmar and India is known as the India-Myanmar border.
In humans and other mammals the thorax and abdomen are separated by a sheet of muscle called the diaphragm. In insects like wasps and bees where there is a narrow region between the thorax and the abdomen this is called the petiole.