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ag·gres·sive

(ə-grĕsĭv)

adj.

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.

ag·gressive·ly adv.

ag·gressive·ness n.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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