Pronunciation: (sem'i-sûr"kul), [key]
1. Also called sem•i•cir•cum•fer•ence Pronunciation: (sem"ē-sur-kum'fur-uns, -fruns, sem"ī-). [key]half of a circle; the arc from one end of a diameter to the other.
2. anything having or arranged in the form of a half of a circle.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.