Pronunciation: (sur-kum'fur-uns), [key]
1. the outer boundary, esp. of a circular area; perimeter: the circumference of a circle.
2. the length of such a boundary: a one-mile circumference.
3. the area within a bounding line: the vast circumference of his mind.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.