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
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
In October 2023, Isabella was hospitalized and underwent an emergency surgery to remove a large medulloblastoma — a type of malignant tumor — in her cerebellum. Vanessa Etienne, People.com, 28 Oct. 2024 Tanton wasn’t just a malignant force against immigration. Abrahm Lustgarten, ProPublica, 19 Oct. 2024 The cells lining the milk ducts turn malignant (cancerous) but stay in place (in situ). Mya Abraham, VIBE.com, 10 Sep. 2024 When the reality star was six months old, doctors discovered that she was born with a malignant glioma on the right side of her brain. Esther Kang, Peoplemag, 24 July 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 5 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

Last Updated: - Updated example sentences
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