Normal. It takes a lot of mass to bend light.
I am pretty sure its a line segment.
A straight line, a telephone line, a shipping line, a fishing line.
a line
In geometry a straight line that touches a curve is called a tangent.
There is no particular name.
Straight
Collinear lines lie on the same straight line.
straight line.
A Linear graph
Straight line
radius
Tangent