Incumbent – English Flashcard for Incumbent for IELTS Updated: September 8, 2020 by Dr. Mohammad Hossein Hariri AslIncumbentIncumbent (adj & noun) /ɪnˈkʌm.bənt/necessary and obligatory – compulsory – mandatory – unavoidable – inescapable – requisite – office holder – appointee:As a simple private, it was incumbent upon me to take orders, no matter what.