1 an expert in a particular subject who is asked by a court of law or other official group to give advice:
The government appointed independent assessors to review the viability of the remaining coal mines.
2 a person who calculates the value or cost of sth or the amount of money to be paid:
an insurance / tax assessor
3 a person who judges how well sb has done in an exam, a competition, etc:
College lecturers acted as external assessors of the exam results.
