📖 Math Dictionary
Diameter
/dy-AM-ih-ter/
Definition
The diameter is a straight line passing through the center of a circle, connecting two points on the edge. It is the longest chord and equals twice the radius (d = 2r).
💡Example
If a circle has a radius of 7 inches, its diameter is 7 × 2 = 14 inches. A pizza with 12-inch diameter has a 6-inch radius.
🎓Used in Grades
Grades 4-10KS2 to GCSEÃ…rskurs 4-9