Judge put away rebel's leader first (4)
I believe the answer is:
rate
'judge' is the definition.
(I know that rate is a type of appraise)
'put away rebel's leader first' is the wordplay.
'put away' becomes 'ate' (put away can mean to eat).
'leader' says to take the initial letters.
'first' means one lot of letters go next to another.
The first letter of 'rebels' is 'r'.
'ate' after 'r' is 'RATE'.
(Other definitions for rate that I've seen before include "Assess or grade" , "Rank; speed" , "standard levy" , "Measure as of value or speed" , "Merit; speed" .)