malignant
adjective
ma·lig·nant
mə-ˈlig-nənt 
1
: tending to produce death or deterioration
malignant malaria
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
There is just too much market demand for evidence that Trump and his works are wholly malignant.
—
The Editors, National Review, 7 July 2025
Common types of adrenal tumors include adrenal adenomas (benign), adrenal carcinomas (malignant and prone to spreading) peochromocrytomas, and paragangliomas.
—Maria Azzurra Volpe, MSNBC Newsweek, 18 June 2025
Shortly after his birth, doctors discovered fluid building up inside the baby boy's head in addition to a malignant tumor that required brain surgery.
—Hannah Sacks, People.com, 23 June 2025
Nevertheless, case reports have described malignant tumors developing within tattoos, including melanomas.
—Jesse Pines, Forbes.com, 13 June 2025
See All Example Sentences for malignant
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The Editors, National Review, 7 July 2025
Common types of adrenal tumors include adrenal adenomas (benign), adrenal carcinomas (malignant and prone to spreading) peochromocrytomas, and paragangliomas.
—Maria Azzurra Volpe, MSNBC Newsweek, 18 June 2025
Shortly after his birth, doctors discovered fluid building up inside the baby boy's head in addition to a malignant tumor that required brain surgery.
—Hannah Sacks, People.com, 23 June 2025
Nevertheless, case reports have described malignant tumors developing within tattoos, including melanomas.
—Jesse Pines, Forbes.com, 13 June 2025
See All Example Sentences for malignant
Cite this Entry
“Malignant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/malignant. Accessed 22 Jul. 2025.
Copy CitationKids Definition
malignant
adjective
ma·lig·nant
mə-ˈlig-nənt
1
: evil in influence or effect : injurious
3
: tending to produce death
malignant tumors
malignantly
adverb
Medical Definition
malignant
adjective
ma·lig·nant
mə-ˈlig-nənt
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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