Pronunciation: (kol"u-sē'um), [key]
1. an ancient amphitheater in Rome, begun a.d. c70 by Vespasian, having the form of an oval 617 by 512 ft. (188 by 156 m).
2. (l.c.) coliseum.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.