A fourth term refers to an additional period served by an elected official beyond their initial three terms in office. In the context of US presidents, it is significant because no president had ever been elected for more than two terms before Franklin D Roosevelt.
Related terms
Twenty-second Amendment: An amendment ratified in 1951 that limited presidents to two terms in office.
Lame Duck Period: The time between when an incumbent president has been voted out of office and when their successor takes over.
Presidential Succession: The order in which individuals assume presidential powers if the president dies or becomes unable to fulfill their duties.