1) attacking or quarrelling without a reason (aggressive)

2) a country, person, deliberately attacking another (aggressor)

3) (of) a disease attacking many people in one area for a time (epidemic)

4) a piece of writing attacking and ridiculing a person (lampoon)

5) very unpleasant; causing offence; used for, connected with, attacking (offensive)

6) (of animals) attacking and killing others (predatory)

7) a worker who strikes; a player in an attacking position (striker)