Its perimeter
contour line
Perimeter
It is called its bounds. In the case of 2 dimensional objects, it is part of the perimeter.
It is an apothem line that connects the center of a polygon to the center of an outer side.
The out edge of a cup is called the 'Rim'.
outline
outline
contour line
contour line
A line that is drawn to show the edge and surface ridges of an object is typically referred to as an "outline" or "contour line." This line helps define the shape and form of the object, providing visual clarity and depth. In art and design, contour lines are essential for conveying three-dimensionality on a two-dimensional surface. They guide the viewer's eye and enhance the understanding of the object's structure.
A margain could be drawn on any edge of a paraghraph.
The outer edge means the furthest most point from the center. The outer edge is usually the end of the object before the dropping off point.
The line that forms the edge of a figure is an edge line. Which forms the figure the has been drawn. You use this line to define a drawing or a figure.
Perimeter
a solid line at the edge of a paragraph.
An outside border is a line or edge that surrounds the outer boundary of an object, such as a document, image, or table. It is often used to define the limits or separation of the object from its surroundings.
A straight line from the center of a circle to the outer edge is called a radius.