malignant

adjective

ma·​lig·​nant mə-ˈlig-nənt How to pronounce malignant (audio)
1
: tending to produce death or deterioration
malignant malaria
especially : tending to infiltrate, metastasize, and terminate fatally
a malignant tumor
2
a
: 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
malignantly adverb

Examples of malignant in a Sentence

a highly malignant form of cancer a powerful and malignant influence
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Her freshman year at USC was cut short in October 2023 after having emergency surgery to remove a large medulloblastoma — a type of malignant tumor — in her cerebellum. Vanessa Etienne, People.com, 20 Nov. 2024 Their administration has spent years appeasing Iran with sanctions relief and turning a blind eye to the malignant activity of the regime and its proxies. The Editors, National Review, 4 Sep. 2024 Extending telomeres could inadvertently allow cells to bypass these safety mechanisms, leading to malignant transformations. William A. Haseltine, Forbes, 16 Aug. 2024 Nor for that matter is pathological liar, sociopath or malignant narcissist. Richard Behar, Forbes, 31 Oct. 2024 See all Example Sentences for malignant 

Word History

Etymology

Late Latin malignant-, malignans, present participle of malignari

First Known Use

1542, in the meaning defined at sense 2c

Time Traveler
The first known use of malignant was in 1542

Dictionary Entries Near malignant

Cite this Entry

“Malignant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/malignant. Accessed 28 Nov. 2024.

Kids Definition

malignant

adjective
ma·​lig·​nant mə-ˈlig-nənt How to pronounce malignant (audio)
1
: evil in influence or effect : injurious
2
3
: tending to produce death
malignant tumors
malignantly adverb

Medical Definition

malignant

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

More from Merriam-Webster on malignant

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