A more thorough explanation:

Definition: Vasseleria is a term used in Law Latin that refers to vassalage, which is the state of being a vassal or feudatory. It can also refer to the service required of a vassal, the territory held by a vassal, vassals collectively, the dominion or authority of a feudal superior over vassals, or political servility and subjection.

Examples:

• A knight who held land from a lord in exchange for military service was a vassal and was in a state of vasseleria.
• The vassaticum or main-rent was the service required of a vassal, such as providing soldiers for the lord's army.
• A fief or fee was the territory held by a vassal as part of their vasseleria.
• The vassals collectively were known as the lord's vasseleria.
• The feudal superior had dominion or authority over their vassals' vasseleria.
• Political servility and subjection were also part of the concept of vasseleria, as vassals were expected to be loyal and obedient to their lord.

These examples illustrate the different aspects of vasseleria, including the relationship between a lord and their vassals, the obligations and services required of vassals, and the political and social hierarchy of feudal society.