Protractor: An instrument used in measuring or drawing angles.
Compass: more accurately known as a pair of compasses, is a technical drawing instrument that can be used to inscribing circles or arcs.
Locus: The locus of points are a certain distance from a central point.
Equidistant: The same distance (from each other, or in relation to other things).
Discorectangle: is a shape constructed of a rectangle with semicircles at a pair of opposite sides.
Perpendicular lines: Two lines that meet at a right angle
Arc: Part of the circumference of a circle.
Construct: means to draw shapes, angles or lines accurately.
Bisect: to divide into two equal parts.
Bisector: The line that divides something into two equal parts.
Congruent: The same shape and size.