A contested incompatibility that entails the use of armed force between two parties including a territory, the government of a state, or both.
A motivational grudge against a person or faction, which may or may not be reciprocated; the state of having it in for someone.
Revenge.
A bitter, destructive feud, normally between two families, clans, or factions, in which each injury or slaying is revenged: a blood feud.