n. In Roman history:n. In general, a commander, chief, or ruler: in this sense a descriptive title (placed after the name) of any one possessing the imperium or power of enforcing his authority, as a general, or a consul, proconsul, or other magistrate.n. In later times, more especially, a general-in-chief or holder of an independent command during active service: a title often conferred by the senate on a victorious general, or acclaimed by his army.n. After the fall of the republic, the official title (used as a prenomen) of the monarch or supreme ruler as permanent generalissimo of the Roman armies; emperor: originally conferred by the senate for a term, and afterward assumed in perpetuity.n. [capitalized] In zoology, a genus of trochiform prosobranchiate gastropods, of the family Turbinidæ. Montfort.