the official who holds an office
"The incumbent senator easily defeated her challenger in the recent election."
The current holder of an office, such as ecclesiastical benefice or an elected office.
"The incumbent senator faced a tough opponent in the upcoming election."
In plain English: An incumbent is someone who currently holds an elected office and is running for re-election.
"The incumbent senator is running for re-election this year."
necessary (for someone) as a duty or responsibility; morally binding
"it is incumbent on them to pay their own debts"
Imposed on someone as an obligation, especially due to one's office.
"As the department head, it is incumbent upon her to submit the final report before Friday."
In plain English: An incumbent is someone who currently holds an elected office and is running for re-election.
"The incumbent administration has promised to lower taxes next year."
Usage: Use "incumbent" only in formal contexts where a duty is tied specifically to holding a particular position; avoid it for general obligations that apply to anyone regardless of role. Do not confuse this adjective with the noun form when referring simply to the current officeholder.
The word "incumbent" comes from the Latin verb incumbere, which literally means to lean or recline upon something. It entered English with its current meaning of a person holding an office, shifting from the original image of someone pressing down on a position.