Imperator n. : A commander; a leader; an emperor; -- originally an appellation of honor by which Roman soldiers saluted their general after an important victory. Subsequently the title was conferred as a recognition of great military achievements by the senate, whence it carried wiht it some special privileges. After the downfall of the Republic it was assumed by Augustus and his successors, and came to have the meaning now attached to the word emperor.

Example:
How old are Boa constrictor Imperator neonates when they first shed their skin?

Taxonomy
Imperator, emperor, Pavo muticus imperator, Boa constrictor imperator, Imperatrix, king, Latin, Augustus, English word, Emperor of India, the Roman Emperors, subspecies, Imperatores, the Roman Empire, free encyclopedia, Ancient Rome, Magistrates, the Roman Republic.

Defination from the web:
Imperator was a title originally roughly equivalent to commander during the period of the Roman Republic. ... Nevertheless, Imperator maintained a relatively constant status as a part of a Roman ruler's title throughout the principate (derived from ...