1. Characterized by aggression: aggressive behavior.
2. Inclined to behave in an actively hostile fashion: an aggressive regime.
3. Assertive, bold, and energetic: an aggressive sales campaign.
4. Of or relating to an investment or approach to investing that seeks above-average returns by taking above-average risks.
5. Fast growing; tending to spread quickly and invade: an aggressive tumor.
6. Characterized by or inclined toward vigorous or intensive medical treatment: an aggressive approach to treating the infection.
7. Intense or harsh, as in color.
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