Seniority is the concept of a person or group of people taking precedence over another person or group because the former is either older than the latter or has occupied a particular position longer than the latter. Seniority is present between parents and children and may be present in other common relationships, such as among siblings of different ages or between workers and their managers.
Under a seniority system, control is often granted to senior persons due to length of service in a given position. When persons of senior rank have less length of service than their subordinates, "seniority" may apply to either concept.
In some military command structures, the length of time someone has held a particular rank is called "seniority in grade" and determines whether that person is senior to another person of the same rank. For instance, a captain who was promoted five years ago can give orders to a captain who was promoted three years ago.
Seniority in United States politics, when used out of context, is informally defined as the number of years one member of a group has been a part of the group. For example, as of January 2015, John Conyers from Michigan is the most senior member of the House of Representatives. However, "seniority" can also refer to political power attained by position within the United States Government. For further details, see:
Seniority is viewed sometimes both positively and negatively. Many elected officials are viewed as retaining their position only because they have been there for many years, which can reflect voter stagnancy and the benefits of incumbency. On the other hand, long years of incumbency can also be seen as a sign of the person's ability to continue pleasing voters or the use of seniority to deliver benefits to constituents.
In some countries the Dean of the Diplomatic Corps receives special treatment.
In unionised companies, employees with more seniority may enjoy more work privileges. Here are examples:
Seniority also has an influence over bumping rights, which is a reassignment of jobs, possibly for many people at a time.