LINE SEGMENTS
- - line to plain or plain to solid
    - angular
    - Round
Discussion

LINE SEGMENTS

Open line segments
closed line segments
- chord , A chord (from the Latin chorda, meaning “bowstring”) of a circle is a straight line segment whose endpoints both lie on a circular arc.
- diagonal , a diagonal is a line segment joining two vertices of a polygon or polyhedron, when those vertices are not on the same edge.
- diameter , a diameter of a circle is any straight line segment that passes through the centre of the circle and whose endpoints lie on the circle.
- radius , a radius (pl.: radii or radiuses)[a] of a circle or sphere is any of the line segments from its center to its perimeter
- edge , an edge is a particular type of line segment joining two vertices in a polygon, polyhedron
half open line segments

line to plain or plain to solid

angular


	middle	Between angles	DIAGONAL.
	extemity	SIDE.

Round

		English word	Latin or greek
	Round; externally touching		TANGENT.
	Round; externally cutting		SECANT.
	Round : intenally - central - side to side -	Ray.	DIAMETER,
	Round ( internally - central - pole to pole )		AXIS.
	Round : intenally - not central - periphery to diameter		SINE.
	Round ( internally - not central - periphery to periphery )		CHORD.