ma·​lig·​nant | \ mə-ˈlig-nənt How to pronounce malignant (audio) \

Definition of malignant

1 : tending to produce death or deterioration malignant malaria especially : tending to infiltrate, metastasize, and terminate fatally a malignant tumor
2a : evil in nature, influence, or effect : injurious a powerful and malignant influence
b : passionately and relentlessly malevolent : aggressively malicious the malignant tongues of gossipers
c obsolete : malcontent, disaffected

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Other Words from malignant

malignantly adverb

Examples of malignant in a Sentence

a highly malignant form of cancer a powerful and malignant influence
Recent Examples on the Web Rules can be bypassed or rewritten—with or without notice, with or without malignant intent, by a few degrees at a time or more than a few. Barton Gellman, Wired, "Inside the NSA’s Secret Tool for Mapping Your Social Network," 24 May 2020 The murder is a crime of passion, a malignant outgrowth of Dmitri’s desire. Ryu Spaeth, The New Republic, "The Unsuitable Passions of J.M. Coetzee," 18 May 2020 Eric Schmitt is to be commended for wanting to make China pay a price in the United States for its malignant role in the current global pandemic. Dan Mclaughlin, National Review, "Missouri’s Misguided Lawsuit Against China," 23 Apr. 2020 One of the first in line, on April 13, was San Jose resident Rosemary Pathy-McKinney, who had a non-malignant brain tumor that clouded her vision and gave her headaches. Mallory Moench,, "Bay Area hospitals rescheduling non-emergency surgeries as health care system reopens from coronavirus," 23 Apr. 2020 The immune system’s delicate balance All infectious diseases spark a biological war in the body between malignant microbes and a potent army of immune molecules. National Geographic, "THE BEST OF NATIONAL GEOGRAPHIC DELIVERED TO YOUR INBOX," 25 Mar. 2020 Well, given the malignant chaos of a purposeless universe, what’s one little false allegation in the scheme of things? USA TODAY, "Read excerpts from Woody Allen's new memoir about Dylan Farrow, Harvey Weinstein and #MeToo," 24 Mar. 2020 The level of containment will depend on how malignant the virus is in its spread and fatality rate, said Dr. John Swartzberg, clinical professor emeritus of infectious diseases and vaccinology at UC Berkeley. Catherine Ho,, "Coronavirus isolation tactics are ramping up in the Bay Area. When does it end?," 10 Mar. 2020 Working in their Stanford lab, Weissman, fellow founder Ravindra Majeti, and Siddhartha Jaiswal identified the role of CD47 proteins in the progression of cancer stem cells into a more malignant form., "Target to limit purchases of hand sanitizer, disinfecting wipes," 10 Mar. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'malignant.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of malignant

1542, in the meaning defined at sense 2c

History and Etymology for malignant

Late Latin malignant-, malignans, present participle of malignari

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Time Traveler for malignant

Time Traveler

The first known use of malignant was in 1542

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Statistics for malignant

Last Updated

4 Jun 2020

Cite this Entry

“Malignant.” Dictionary, Merriam-Webster, Accessed 4 Jun. 2020.

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How to pronounce malignant (audio)

English Language Learners Definition of malignant

medical : very serious and dangerous : tending or likely to grow and spread in a rapid and uncontrolled way that can cause death
formal : very evil


ma·​lig·​nant | \ mə-ˈlig-nənt How to pronounce malignant (audio) \

Kids Definition of malignant

2 : likely to cause death : deadly

Other Words from malignant

malignantly adverb


ma·​lig·​nant | \ mə-ˈlig-nənt How to pronounce malignant (audio) \

Medical Definition of malignant

1 : tending to produce death or deterioration malignant malaria especially : tending to infiltrate, metastasize, and terminate fatally malignant tumors — compare benign sense 1
2 : of unfavorable prognosis : not responding favorably to treatment psychotic reactions with a malignant trend

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