circle vocab

3. A secant line is a straight line joining two points on a function.
7. There are a number of meanings for the word "arc" in mathematics.
9. Concentric circles are circles with a common center. The region between two concentric circles of different radii is called an annulus.
10. the enclosing boundary of a curved geometric figure, especially a circle.
11. a ring-shaped object, structure, or region.
12. In geometry, a centre of an object is a point in some sense in the middle of the object.
13. a straight line passing from side to side through the center of a body or figure, especially a circle or sphere.

1. In geometry, the tangent line (or simply tangent) to a plane curve at a given point is the straight line that "just touches" the curve at that point.
2. a half of a circle or of its circumference.
4. An inscribed angle is an angle formed by two chords in a circle which have a common endpoint.
5. The number π is a mathematical constant.
6. A central angle is an angle with endpoints and located on a circle's circumference and vertex located at the circle's center
8. a straight line from the center to the circumference of a circle or sphere.
12. a group of (typically three or more) notes sounded together, as a basis of harmony.