The period of a pope's term in office is called a papacy. There is no fixed term length, as a pope serves for life unless he resigns or is otherwise unable to fulfill his duties. The papacy continues until the death or resignation of the pope, after which a new pope is elected.
The period of time during which a president is in charge is called his (or her) term of office.
The two-year period between congressional elections is known as a term. This is the period which the elected officials will hold office.
A term
This is called "term of office" and varies from job to job.
There is no widely used term for such a period.
The two-year period between congressional elections is known as a term. This is the period which the elected officials will hold office.
An assigned period of time for an elected official is called a term.
"time" or "time period" in office is the simple replacement. "tenure" in office might be what you want. His time in office is also referred to as his "administration" .
It is a term in office.
Campaign
In America, presidents serve for a four year period called a "term." President Obama's first term was his first four years in office, beginning in 2008. He was re-elected in 2012, and began his second term officially on January 20, 2013.
His term of office is four years. There is a so-called two-term limit that limits a person to a maximum of ten years in the office of president. That is, a person who has never previously held the office of president or has served two years or less finishing another president's term may be elected a maximum of two times. A person that has served more than two years finishing another president's term may be elected to the office only once.