The Caesar's Legion have created their own language, a combination of English, Latin and some particular terms adapted from Roman history, used in everyday communication. The following is an exhaustive glossary of Caesar's Legion terms, together with their translations (where applicable).
- Aeternit imperi: eternal authority; referring to the perpetual authority of Caesar on the Legion and used as an inscription in the Legion aureus.
- Amicus: friend; used to refer to an trusted independent ally of the Legion.
- Ave: hail; used as a greeting.
- Caesar dictator: dictator Caesar or absolute ruler Caesar; used as an inscription in the Legion denarius.
- Capture, Captures: a term for persons that were captured during Legion raids and have yet to be trained into proper slaves.
- Cedo Nulli: I yield to no one, spoken by the Silus by passing an intelligence check.
- Damnatio memoriae: condemnation of memory; used to denote archenemies of the Legion, slated for elimination and erasure from history. A declaration on a person or group that marks them as an enemy of Caeser's Legion in perpetuity. This is only given to those who aid and abet known enemies of Caesar's Legion. Many legionaries will attempt to assassinate those declared in damnatio memoriae as a sign of loyalty to the Legion.
- Decimatio: decimation derived from Latin meaning "removal of a tenth", it was a form of military discipline used by officers in the Roman Army to punish mutinous or cowardly soldiers, used by the Legate in the Caesar's Legion against legionaries of an undisciplined officer. The Legate step to beat the failed commander to death in front of his assembled troops and after orders the decimatio. The legionaries are lined up in ranks. Every tenth man steps forward and is beaten to death by his comrades, instilling a robust obedience.
- Dissolute: from the Latin dissolutus, an immoral, degenerate person; a term used to refer to people who are not members or subjects of the Legion.
- Divide et impera: divide and conquer, an expression coined by the Roman military and political leader Gaius Julius Caesar. It is a combination of political, military, and economic strategy of gaining and maintaining power by breaking up larger concentrations of power into chunks that individually have less power than the one implementing the strategy.
- Et cetera: Latin expression that means and other things or and so forth; abbreviated as etc. in common language.
- Honestas, Industria, Prudentia: Honesty, Industry, Prudence; three virtues of slaves of the Caesar's Legion.
- In hoc signo taurus vinces: under the sign of the bull you will win; an adaptation of the Roman Emperor Constantine the Great's motto "In hoc signo vinces" incorporating the symbol of the Caesar's Legion, meaning that only those under the banner of the Caesar's Legion will win.
- Magnum chasma: great abyss or great fissure; referring to the Grand Canyon and used as an inscription in the Legion denarius.
- Pax Per Bellum: peace through war, an expression based on the Latin Si vis pacem para bellum meaning if you want peace prepare for war; it is one of the mottoes of the Caesar's Legion and used as an inscription in the Legion aureus.
- Pax Romana: Roman peace, it was a long period of relative peace and minimal expansion by military force experienced by the Roman Empire in the 1st and 2nd centuries AD; Pax Romana in the Legion meaning long-term stability at all costs.
- Profligate: from the Latin profligatus, a wasteful, shamelessly immoral person; term used to refer to enemies of the Legion, most notably the NCR.
- Rubicon: shortening of "crossing the rubicon" expression based on the Latin alea iacta est meaning the die is cast; Rubicon in the Legion meaning that events have passed a point of no return and that something inevitable will happen, especially used by Caesar to talk about the war against the NCR.
- Salve: hail meaning "take care of yourself, be in health"; used during a battle to greet a comrade.
- Vale: farewell.
Titles and ranks
- Caesar: The title bestowed upon the supreme dictator of the Legion and Son of Mars. As of 2281, only Edward Sallow has held the title of Caesar.
- Centurion: chief of a hundred; an officer rank in the Legion he had 10 Decanii in his command.
- Cursor: runner or messenger; used by the Legion as a title for a legionary who ferries along the Colorado River.
- Decanus: chief of ten; an officer rank in the Legion he had 10 Legionaries in his command.
- Frumentarii: from the Latin frumentarius, originally a soldier responsible for the collection of wheat owed to the Roman state by farmers, but later became to a military intelligence operative since Emperor Hadrian; used by the Legion as the name of their special forces operatives.
- Legatus: often spelled Legate; a high-ranking Roman military officer in the Roman Army, equivalent to a modern high-ranking general officer. Caesar's Legion uses the rank much the same way. There have only been two Legates in the history of Caesar's Legion: the Malpais Legate and Legate Lanius. Legatus are in command of cohorts that disseminate their orders to centurions in charge of Centuriae.
- Praetorian: derived from Latin praetoriani, it was a force of bodyguards used by Roman Emperors; used by the Legion as the name of Caesar's personal guards.
- Speculatores: spies; ancient Roman scouts that also performed reconnaissance of enemy movements when needed. They are used much the same way in the Legion. They are never seen properly in any game, but are known to exist and likely the reason for reports of the Courier's activity to Caesar.
- Vexillarius: flag bearer; legionary carrying the standard of the Legion into battle.
- Cohort: the largest division of Roman soliders, a cohort was a standard tactical military unit of a Roman legion, though the standard changed with time and situation, and was composed of between 360-800 soldiers. In Caesar's Legion a cohort numbers 480 men and are commanded by a Legate. It is then divided into 6 Centuriae.
- Centuriae: the midsized organized unit of soldiers in the Roman Army that originally composed 100 legionaries (as the name suggests), but became to only represent 80 men. Caeser's Legion's division is based on the 80 men division and led by a Centurion. It is then further divided in to 10 contubernia.
- Contubernia: the smallest organized unit of soldiers in the Roman Army and was composed of 8 legionaries (tent groups) led by a Decanus. Used much the same way in Caesar's Legion.