The line between countries is called a "border." Borders can be defined by natural features, such as rivers and mountains, or by artificial means, such as treaties and agreements. They serve as boundaries for political, legal, and economic purposes, often influencing trade, Immigration, and governance.
It is called a border.
The portion of a line that falls between two points is called a line segment.
A line segment
the measure of a straight-line distance between two points is called length.
the distence between two point called line.
It is called a border.
The Border between the two countries separating Russia and China is just that a Border line.
border ..
borders
A line between two verticies is called a line segment.
The portion of a line that falls between two points is called a line segment.
The line is called the terminator
It's the line (boundary) between two countries.
India and china
Radcliffe line separates India and Pakistan
It is called a vinculum.
Durand Line ,,