Grade — level (4)
I believe the answer is:
tier
I believe this clue is a double definition.
'grade' is the first definition.
(I know that grade can be written as tier)
'level' is the second definition.
(I know that level can be written as tier)
(Other definitions for tier that I've seen before include "I might draw" , "One of two or more rows" , "Person joining" , "Row, level" , "Bank - row" .)