grader
A person who checks and scores tests or other work.
A grader is a heavy machine used to level and smooth dirt, gravel, or pavement. Road crews use graders to prepare surfaces before laying asphalt, and construction workers use them to flatten land for new buildings. These machines have a long blade underneath that scrapes the ground flat as they drive forward.
A grader can also be a person who grades or evaluates work. Your teacher acts as a grader when marking your spelling test, and judges at a county fair are graders when they score entries in competitions.
As a verb, to grade means to level or smooth a surface, or to evaluate and score someone’s work.