radius
Additional answer
Actually, the radius is the line that joins the centre to the circumference. The line that compasses draw to trace a circle is just that, a circle.
All points in a plane that are equidistant from a given point form a circle. The center of the circle is the given point, and the radius is the constant distance from the center to any point on the circle. Thus, every point on this circle maintains the same distance from the center point.
Round. A more detailed definition is that it is the set of all points that are at a given distance (the "radius") from a given point (the "center").
There are an infinity of points 4cm from a given line. These points form 2 lines parallel to and either side of the original line. Equally, there are an infinite number of points 4cm from a given point on the original line. These points lie on the circumference of a circle radius 4cm with its centre at the given point. There are only 2 points that fulfil both conditions. These points are found on the circumference of the circle where a diameter perpendicular to the original line and passing through the given point meets the circumference of the circle. These two points are also where the two parallel lines form tangents with the circle.
The three vertices of a circle are at the same distance form each other. The circumference of a circle identifies all points which are at a given distance from a point (vertex).
The three-dimensional form of a circle is a cylinder.
The circumference.
The plural possessive for compasses is compasses'.
The possessive form of compass is compass's.
Compasses is the plural form of compass.
The plural form of the noun compass is compasses.The plural possessive form is compasses'.Example: The compasses' cases are made of brass.
An astroid is a hypocycloid with four cusps - a particular form of plane curve traced from a fixed point on a circle.
A circle.
The plural of compass is compasses, and the plural posessive is compasses'(referring to more than one compass).
Join the centre of the circle O and the point A .Extend it to both sides to form a line.This is the required locus
Compass
All points in a plane that are equidistant from a given point form a circle. The center of the circle is the given point, and the radius is the constant distance from the center to any point on the circle. Thus, every point on this circle maintains the same distance from the center point.
A circle or a sphere would seem to fit the given conditions