Incumbency (noun)

1. The condition of being in a particular office or position.
2. The time during which someone holds a particular office or position.

Origin:

Late 16th century from latin incumbere "to lie upon", from in- "on" + a second element related to cubare "to lie down".

Examples:

1. The incumbency of the president ended after 8 years.
2. Her incumbency was marked by major reforms in the education sector.
3. He was well known for his ability to perform his duties with the highest degree of efficiency during his incumbency.
4. The incumbency of the mayor was known for its emphasis on public safety.
5. Her incumbency as governor was marked by a number of reforms aimed at improving the standard of living in the state.