Pronunciation: (dek'yoo-mun), [key]
1. large or immense, as a wave.
2. (in ancient Rome) of or pertaining to the tenth cohort of a legion.
Also called dec'uman gate'. (in ancient Rome) the main gate of a military camp, facing away from the enemy and near which the tenth cohort of the legion was usually stationed.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.