Definitionen
1.NounAn indefeasible right or title, distinguished from a contingent interest, which could be defeated (i.e. cease) if a certain event occurred.
2.NounA fixed right granted to an employee, especially under a pension plan.
3.NounA stake, often financial, in a particular outcome.
4.NounA group of people or organizations with such a stake, especially those that seek to control an existing system or activity from which they derive benefit.
5.NounAn exceptionally strong interest in protecting or promoting something to one's own advantage.