Pro tempore or pro tem is a latin phrase which best translates to "for the time being" in English. This phrase is most often used in politics to describe a person who acts as a locum tenens (placeholder) in the absence of a superior, such as a President pro tempore of the United States Senate. Locum tenens is a Latin phrase literally meaning holding place. ... Ted Stevens, the current President pro tempore of the United States Senate. ...
In the United States, the President protempore of the Senate is the second-highest-ranking official of the upper house of Congress, the Senate.
The President protempore is an office of the Senate mandated by Article I, section 3 of the Constitution.
The President protempore, together with the Speaker of the House, is the authority to which declarations of presidential inability are transmitted in accordance with the 25th Amendment to the Constitution.
Protempore is a Latin term meaning "for the time being"; thus, the occupant of the position was conceived as a temporary presiding officer.
Since 1816, presidents protempore have received a larger salary than other senators, and, for a period after 1856, they were compensated at the same rate as the vice president.
The president protempore works closely with the secretary and the sergeant at arms of the Senate, directing the enforcement of the rules governing the use of the Capitol and the Senate office buildings.