Clockwise — Definition, Meaning & Examples

Clockwise

The direction that the hands of a clock move.

See also

Example

Problem: Triangle ABC has vertices A(1, 3), B(4, 3), and C(4, 1). Describe the order in which you encounter the vertices when tracing the triangle clockwise starting from A.

Step 1: Plot the points. A is at the upper left, B is at the upper right, and C is at the lower right.

Step 2: Starting at A and moving clockwise (right first, since A is at the top-left), you reach B, then move down to C, then back up-left to A.

Answer: Tracing the triangle clockwise from A gives the order A → B → C → A.

Why It Matters

Clockwise and counterclockwise directions matter whenever you describe rotations in geometry. A 90° clockwise rotation produces a different image than a 90° counterclockwise rotation. Specifying the direction also matters in real-world contexts like tightening screws (clockwise) or reading angles in trigonometry.

Common Mistakes

Mistake: Confusing clockwise with counterclockwise when performing rotations on a coordinate plane.

Correction: Remember: clockwise goes in the same direction clock hands move (top → right → bottom → left). A 90° clockwise rotation about the origin maps the point

(x, y)

(y, -x)

, while a 90° counterclockwise rotation maps it to

(-y, x)

Related Terms

Counterclockwise — The opposite direction of rotation
Rotation — A transformation that turns a figure around a point
Angle — Measured by the direction of rotation between rays
Transformation — General term for moving or changing a figure