Aggressor

google

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mid 17th century: from late Latin, from aggredi ‘to attack’ (see aggression).

wiktionary

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From Latin aggressor(“attacker, assailant, aggressor”)

etymonline

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aggressor (n.)

1670s, "person who first attacks," from Latin aggressor, agent noun from past participle stem of aggredi "to approach; to attempt; to attack" (see aggression).