From Halopedia, the Halo wiki
Aristocrats are the higher members of society, such as the nobility and upper class. In human society, Aristocrats are rare, usually possessing hereditary titles. In Sangheili culture, Aristocrats earn their high status through martial prowess.
In Sangheili culture, Aristocrats are the only ones permitted to wield an energy sword outside the military. Upon being given their title, Aristocrats have the suffix "-ai" added to their name; this is not replaced by the "-ee" suffix if they enter military service. Once an Aristocrat is given his personal energy sword, he is no longer eligible for marriage for ceremonial reasons, but is permitted to mate with any female they wish, married or unmarried, in order to pass his "Swordsman" genes down to the next generation and kin. Within the military, aristocratic title is not necessary for wielding an energy sword.
- Main article: Human
Originally, the term Aristocrat was used to describe the young men of the ruling class in Athens, Greece, who lead their armies with their swords down. It later passed into usage as an alternate word for the "nobility" of the Middle-Ages and is today recognized as the description of a descendant of one of 7,000 families with hereditary titles in Britain and other European countries that still acknowledge hereditary titles. As a Knight and Lord, Fleet Admiral Hood can be considered a human Aristocrat.