Matching Pairs Geometry part 1 of circle unit vocabOnline version study geometery circle vocab by Hannah Schmidt 1 Inscribed angle 2 Tangent 3 Radius 4 Central angles 5 Chord 6 Point of tangency 7 Secant 8 Diameter a line perpendicular to a radius and only touches the circumference once Segment connecting center to circumference segment connecting 2 points on the circumference and through the center segment connecting any 2 points on the circumference angle whose vertex IS the center of the circle -the measure of a circle is EQUAL to the measures of the intercepted arc line intersecting a circle twice angle whose vertex is on the circumference of the circle - The measure of an inscribed angle is HALF of the intercepted arc the location where the tangent line touches the circumference