Accomplice
'accomplice' is the definition.
(I know that abettor is a type of accessory)
This is all the clue.
(Other definitions for abettor that I've seen before include "One aids another" , "Associate" , "Accomplice" , "fellow-criminal" , "Assistant" .)
'accomplice' is the definition.
(I know that accessory is a type of accomplice)
This is the entire clue.
(Other definitions for accessory that I've seen before include "Hat or handbag, say" , "Matching gloves, for example" , "Criminal's helper" , "Supplementary component of clothing" , "One assisting a crime" .)