adverse

[ ad-vurs, ad-vurs ]

/ ædˈvɜrs, ˈæd vɜrs /

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adjective

unfavorable or antagonistic in purpose or effect: adverse criticism.

opposing one's interests or desire: adverse circumstances.

being or acting in a contrary direction; opposed or opposing: adverse winds.

opposite; confronting: the adverse page.

Nearby words

adversarial, adversary, adversaryism, adversative, adversative asyndeton, adverse, adverse possession, adverse pressure gradient, adverse reaction, adverse selection, adversity

Origin of adverse

1350–1400; Middle English < Anglo-French, Old French advers < Latin adversus hostile (past participle of advertere), equivalent to ad- ad- + vert- turn + -tus past participle suffix, with -tt- > -s-

SYNONYMS FOR adverse

1 hostile, inimical, unfriendly.

2 unfavorable; unlucky, unfortunate; disastrous, calamitous, catastrophic.

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ANTONYMS FOR adverse

1–3 favorable.

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Related forms

ad·verse·ly, adverbad·verse·ness, nounun·ad·verse, adjectiveun·ad·verse·ly, adverb

un·ad·verse·ness, noun

Can be confused

adverse averse (see usage note at the current entry)

Synonym study

2. See contrary.

Usage note

The adjectives adverse and averse are related both etymologically and semantically, each having “opposition” as a central sense. Adverse is seldom used of people but rather of effects or events, and it usually conveys a sense of hostility or harmfulness: adverse reviews; adverse winds; adverse trends in the economy. Related nouns are adversity and adversary: Adversities breed bitterness. His adversaries countered his every move. Averse is used of persons and means “feeling opposed or disinclined”; it often occurs idiomatically with a preceding negative to convey the opposite meaning “willing or agreeable,” and is not interchangeable with adverse in these contexts: We are not averse to holding another meeting. The related noun is aversion: She has a strong aversion to violence. Averse is usually followed by to, in older use occasionally by from.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for adverse

“Any time you put a foreign substance into anybody you have the potential for an adverse event,” Geisbert reminds.
Uh Oh: Ebola Vaccine Trials Stop|Leigh Cowart|December 19, 2014|DAILY BEAST
Human trials of the Ebola vaccine have been temporarily shut down due to adverse side effects.
Uh Oh: Ebola Vaccine Trials Stop|Leigh Cowart|December 19, 2014|DAILY BEAST
However, just because a vaccine is replication-defective does not mean that you won't have an adverse event.
Uh Oh: Ebola Vaccine Trials Stop|Leigh Cowart|December 19, 2014|DAILY BEAST
For the individual patient, there is the potential for side effects or adverse reactions.
Without Education, Antibiotic Resistance Will Be Our Greatest Health Crisis|Russell Saunders|December 19, 2014|DAILY BEAST

Reeve passed away after experiencing an adverse reaction to an antibiotic on Oct. 10, 2004.
Robin Williams and Christopher Reeve's Epic Friendship and the Greatest Williams Story Ever Told|Marlow Stern|August 12, 2014|DAILY BEAST
The position of those who remained was regulated in a series of decrees, adverse to the system, but favourable to the inmate.
Lectures on the French Revolution|John Emerich Edward Dalberg-Acton
Under these, adverse at every point, we are required to carry these two races in peace and honor to the end.
The Art of Public Speaking|Dale Carnagey (AKA Dale Carnegie) and J. Berg Esenwein
It was only when Blake spoke with equal licence of the sex passion that Linnell felt an adverse tug at their friendship.
William Blake|Charles Gardner
Custance was prepared to accept this as an adverse judgment, and to bow to Mr. Jackson's decision; for he was a man of honour.
Grey Town|Gerald Baldwin
Verily, my expedition was pursued by adverse fortunes, and it seemed as if the Fates had determined upon our return.
How I Found Livingstone|Henry M. Stanley

British Dictionary definitions for adverse

adverse

/ (ˈædvɜːs, ædˈvɜːs) /

adjective

antagonistic or inimical; hostileadverse criticism

unfavourable to one's interestsadverse circumstances

contrary or opposite in direction or positionadverse winds

(of leaves, flowers, etc) facing the main stemCompare averse (def. 2)

Derived Forms

adversely, adverbadverseness, noun

Word Origin for adverse

C14: from Latin adversus opposed to, hostile, from advertere to turn towards, from ad- to, towards + vertere to turn

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