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Synonyms

unethical

American  
[uhn-eth-i-kuhl] / ʌnˈɛθ ɪ kəl /

adjective

  1. lacking moral principles; unwilling to adhere to proper rules of conduct.

  2. not in accord with the standards of a profession.

    She treated patients outside the area of her training, and the appropriate medical organization punished her unethical behavior.


unethical British  
/ ʌnˈɛθɪkəl /

adjective

  1. not ethical; improper

    companies involved in unethical practices

"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

Other Word Forms

Etymology

Origin of unethical

un- 1 + ethical

Compare meaning

How does unethical compare to similar and commonly confused words? Explore the most common comparisons:

Explanation

Eating the last cookie without sharing? That's just mean. But if you stole that cookie and then lied about it, that would be morally wrong, or unethical. The prefix un- means "not," so something or someone who's unethical is literally "not ethical." In other words, that someone is lacking principles or morals. Because being unethical involves going against social or professional expectations of what's right, it's a word that's often used to describe bad behavior or immoral conduct. So like the great philosophers, you can decide if Cookie Monster has an ethics problem — or just bad eating habits.

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Vocabulary lists containing unethical

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

According to reporting from Politico, at least one travel-related company declined to sponsor the venture after concluding it was unethical.

From Salon • May 18, 2026

Private-equity funds have also been accused of unethical behavior in their aggressive pursuit of profits at all costs.

From MarketWatch • Apr. 24, 2026

It would have thus been unethical to give some patients an anti-PD-1 drug alone merely to serve as a control group.

From The Wall Street Journal • Apr. 21, 2026

Virtually every AI super-brain created has been shown to lie, deceive, and in general behave in disturbing and unethical ways when put in the right conditions.

From Los Angeles Times • Apr. 10, 2026

Even though Bobby felt Paramount’s behavior was unethical and unfair, he took no legal action.

From "Endgame" by Frank Brady

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