10 terms

Circle

the set of coplanar points equidistant from a given point

Radius

the distance from the center point

Chord

segment who endpoints lie on a circle

Diameter

a chord that contains the center of the circle

Secant

a line that intersects a circle in two points

Tangent

in a plan, a line that intersects a circle at exactly one point

Point of Tangency

the point where the tangent line intersects the circle

Common Tangent

two or more circle that share same tangent line

Congruent Circles

circles that have congruent radii

Concentric Circles

circles that lie in same plane & have same center point