malignant

adjective
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

Supreme Court Associate Justice Ruth Bader Ginsburg has been treated for a malignant tumor discovered on her pancreas, the Supreme Court announced on Friday. Christina Oehler, Health.com, "Ruth Bader Ginsburg Was Just Treated for A Malignant Tumor on Her Pancreas, Says Supreme Court," 23 Aug. 2019 My mother, Helen, had been diagnosed with a malignant brain tumor. John Cherwa, Los Angeles Times, "Racing! Welcome back to Golden Gate," 15 Aug. 2019 Nancy’s marrow was faltering, but no malignant cells were occupying it. Siddhartha Mukherjee, The New Yorker, "The Promise and Price of Cellular Therapies," 15 July 2019 In 2006, after his then five-year-old daughter overcame a malignant brain tumor that was expected to kill her, Sestak retired from the Navy after 31 years and contemplated his next move. Jim Geraghty, National Review, "Joe Sestak: The Most Interesting Democrat You Forgot Was Running," 6 Aug. 2019 Research is also picking up on cancer stem cells, malignant cells that resemble stem cells. San Diego Union-Tribune, "As state funding runs out, California stem cell scientists get $30 million gift," 26 June 2019 Children with cancers that may form malignant cells in their testes, for example, shouldn't have that material grafted back into their body, so other methods are being developed to tackle this issue. National Geographic, "First primate born using frozen testicle technique," 21 Mar. 2019 The tumors are usually noncancerous (benign), but sometimes can become cancerous (malignant). Eric Todisco, PEOPLE.com, "Paraguay Man Bullied for His Massive Tumors Has Surgery to Remove 6 Lbs. of Tissue," 14 June 2019 Early multicellular organisms would also have needed to develop defenses against invading malignant cells from other organisms, or transmissible cancers. Jon Kelvey, Smithsonian, "The Evolution of Sex Could Have Provided a Defense Against Cancer Cells," 11 June 2019

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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More Definitions for malignant

malignant

adjective

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

malignant

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

Kids Definition of malignant

1 : malicious
2 : likely to cause death : deadly

Other Words from malignant

malignantly adverb

malignant

adjective
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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