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definitions

aggressive

[uh-gres-iv]
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adjective

characterized by or tending toward unprovoked offensives, attacks, invasions, or the like; militantly forward or menacing: aggressive acts against a neighboring country.
making an all-out effort to win or succeed; competitive: an aggressive basketball player.
vigorously energetic, especially in the use of initiative and forcefulness: an aggressive salesperson.
boldly assertive and forward; pushy: an aggressive driver.
emphasizing maximum growth and capital gains over quality, security, and income: an aggressive mutual fund.
Medicine/Medical.
  1. (of a disease or tumor) spreading rapidly or highly invasive; difficult or impossible to treat successfully.
  2. pertaining to a risky surgery or treatment, or to a medication that has grave side effects: aggressive chemotherapy.

Origin of aggressive

First recorded in 1815–25; aggress(ion) + -ive
Related formsag·gres·sive·ly, adverbag·gres·sive·ness, ag·gres·siv·i·ty [ag-re-siv-i-tee] /ˌæg rɛˈsɪv ɪ ti/, nounan·ti·ag·gres·sive, adjectivean·ti·ag·gres·sive·ly, adverban·ti·ag·gres·sive·ness, nounhy·per·ag·gres·sive, adjectivehy·per·ag·gres·sive·ly, adverbhy·per·ag·gres·sive·ness, nouno·ver·ag·gres·sive, adjectiveo·ver·ag·gres·sive·ly, adverbo·ver·ag·gres·sive·ness, nounpre·ag·gres·sive, adjectivepre·ag·gres·sive·ly, adverbpre·ag·gres·sive·ness, nounpseu·do·ag·gres·sive, adjectivepseu·do·ag·gres·sive·ly, adverbsu·per·ag·gres·sive, adjectiveun·ag·gres·sive, adjectiveun·ag·gres·sive·ly, adverbun·ag·gres·sive·ness, noun
Can be confusedaggressive passive

Synonyms for aggressive

1. pugnacious, militant. 2. forceful, enterprising, assertive.

Antonyms for aggressive

1. friendly. 2. retiring, shy, timid, hesitant.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for hyperaggressive

aggressive

adjective

quarrelsome or belligerentan aggressive remark
assertive; vigorousan aggressive business executive
Derived Formsaggressively, adverbaggressiveness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for hyperaggressive

aggressive

adj.

1791, from Latin aggress-, past participle stem of aggredi (see aggression) + -ive. In psychological use from 1913, first in translations of Freud. Related: Aggressively; aggressiveness.

Online Etymology Dictionary, © 2010 Douglas Harper
hyperaggressive in Medicine

aggressive

[ə-grĕs′ĭv]

adj.

Characterized by aggression.
Inclined to behave in a hostile fashion.
Tending to spread quickly, as a tumor; fast-growing.
Characterized by or inclined toward vigorous or intensive medical treatment.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.