Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun aggressor

2 senses of aggressor

Sense 1
attacker, aggressor, assailant, assaulter -- (someone who attacks)
       => wrongdoer, offender -- (a person who transgresses moral or civil law)

Sense 2
aggressor -- (a confident assertive person who acts as instigator)
       => instigator, initiator -- (a person who initiates a course of action)