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Synonyms

murderous

American  
[mur-der-uhs] / ˈmɜr dər əs /

adjective

  1. of the nature of or involving murder.

    a murderous deed.

  2. guilty of, bent on, or capable of murder.

  3. extremely difficult, dangerous, or unpleasant.

    murderous heat.


murderous British  
/ ˈmɜːdərəs /

adjective

  1. intending, capable of, or guilty of murder

  2. informal very dangerous, difficult, or unpleasant

    a murderous road

"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 murderous

First recorded in 1525–35; murder + -ous

Explanation

A person who's murderous is cruel and violent enough to kill someone. If you are experiencing a murderous rage, it's best to stay inside and away from the public. A murderer, someone who kills deliberately, can be described as murderous. You can also use this adjective in an exaggerated way, simply to emphasize how mad someone is, like when you describe your brother's murderous expression when he realizes you've eaten the last of his Halloween candy. Murderous comes from murder, which in turn has its roots in the Old English morðor, "unlawful killing."

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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.

Running from murderous in-laws is nothing compared to the threat at the heart of “Something Very Bad is Going to Happen,” which depicts exchanging vows with a presumed soul mate as gambling with a curse.

From Salon • Apr. 23, 2026

The upbeat vibe is markedly different from the apocalyptic, at times murderous, sci-fi of today.

From The Wall Street Journal • Mar. 30, 2026

Despite the government's insistence its targets were part of an illicit and murderous network, residents tell a different story.

From Barron's • Mar. 20, 2026

To be clear, the incident, shown from a couple different angles, does not show murderous intent from the driver.

From Slate • Jan. 7, 2026

His work ethic was set at the same high level as those relatives of his who put in murderous hours inside their taverns, pizza joints, and hoagie shops.

From "Drama High" by Michael Sokolove

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