A more thorough explanation:

Definition: Feude is a term related to feudalism, which refers to a heritable estate in land conveyed from a feudal superior to a grantee or tenant, held on the condition of rendering services to the superior. It can also refer to an enmity or private war existing between families or clans, especially as a result of a murder.

• Impartible feud: An indivisible feud; a feud not subject to partition.
• Improper feud: A nonmilitary feud; a feud that is base or servile in nature.
• Proper feud: A feud based on military service.
• Blood feud: A state of hostility between families in which one family seeks to avenge the killing of one of its members by killing a member of the other family.

These examples illustrate the different types of feuds that existed in feudal societies. The impartible feud was an estate that could not be divided, while the improper feud was a nonmilitary feud that was considered base or servile. The proper feud was based on military service, and the blood feud was a state of hostility between families that sought revenge for a murder. These examples show how feuds were an important part of feudal societies and how they could take on different forms depending on the circumstances.